Factory markings
As mentioned in the general information, there are several groups of factory markings. They are:
1) Main markings that were present in production drawings starting in 1935 (before 1935 they were not mentioned in drawings);
2) Operational markings and proofmarks;
3) Markings about a specific rifle/carbine configuration (training, sniper, etc.);
Now more details about these markings groups.
1. Main factory markings that were present in production drawings were mandatory for all manufacturers. The image on the right shows an example of such a list. It shows the ID of each marking (how it was marked in the parts drawings) and a sample of how the marking should look. From the top to bottom they are:
- factory emblem;
- personal marking the quality control department chief;
- personal marking of the quality control worker;
- steel lot number (steel that was used for the production);
- production year;
- test with two strengthen cartridges* markings;
- rifle's serial number;
- accuracy test markings;
- powder test marking (after 1940 it was replaced with the VD cartridge* test marking).
*Strengthen and VD cartridges are variations of proof cartridges, which provided excessive pressure in the barrel.
List of the mandatory markings from 1936 drawings
Sample of the markings placement from the drawings
The easiest markings to spot from this group are the factory emblems, production year and serial numbers. According to factory drawings, the production year was stamped on the barrel shank and on the underside of the receiver tang. The production year stamping on stocks, like those done by the Tula factory, was not required by the drawings. That's a good example showing that factories were not prohibited from using additional markings, their type and location were established by local instructions.
The receiver tang was stamped with a factory marking and production year only after a barrel was attached to it, stamps on the barrel shank were added later. Some rifles have different dates on the barrel shank because the receiver was attached to the barrel when it was not dated. While the production process continued the year ended and a new one begun.
Factory emblems were stamped on many parts of the rifle. There were two types of factory emblems, big (which looked different on different parts) and small. Big factory emblems were stamped on the barrel and the stock (during the M91 production period they were stamped on the receiver as well), small emblems were stamped on smaller parts.
The big emblem of the Tula factory was star with an arrow inside, the big emblems of the Izhevsk factory was a wreath with a hammer and sickle inside, and a triangle with an arrow inside (triangle with arrow was not used on stocks). Small factory emblems were star without an arrow for Tula, and triangle with arrow for Izhevsk.
The above mentioned factory emblems were used on rifles and carbines in the 1930's and 1940's, they were adopted in 1928 when both factories changed their emblems, compared with their earlier ones. During the earlier period, since 1919, Izhevsk used a "wheat with hammer and sickle" stamp on the barrel shank, receiver, and stock. In 1928 the stamping on the receiver was eliminated, the stamp on the stock was modified, circular Р.С.Ф.С.Р letters were added (Russian Soviet Federative Socialist Republic). The imperial pattern "bow and arrow" emblem was used as a part of the big factory emblem and as a small emblem
In the 1920's Tula used the full name of the factory (Tula Foremost Ordnance Factory) with a star above as a part of the main logo on the barrel shank, while the receiver was stamped with big hammer (used since 1918). The same hammer was used on the stock. In 1926 a "big hammer" marking on the front of the receiver was changed to a "wheat with hammer and sickle" marking, quite similar to the Izhevsk "wheat with hammer and sickle". In 1928 the receiver stamp was eliminated, Imperial pattern small hammer markings on smaller parts and big hammer marking on the stock were changed to "star" (smaller parts) & "arrow in star" (stock and barrel) markings. However, some 1929 rifles can still have the old pattern logo. More details will be provided in a future M91 reference section.
Placement of the main factory markings. Non refurbished factory original condition rifle.
Photo courtesy - Ryan Elliott.
Typical receiver tang marking
Izhevsk factory barrel shank markings.
Shape of the wheat, hammer and sickle can be little different. Production year stamp can also have some differences - sometimes a shortened abbreviation for year "г" ("год") was stamped, sometimes not, sometimes it had the dot after, sometimes not. The font of the production year stamp was also different in different years. These differences do not have any effect on value.
Izhevsk factory "triangle in arrow marking".
On the right - Imperial pattern "bow and arrow" marking (used before 1928 and early 1928), the rest are "arrow in triangle" 1928 and later markings from different years.
Izhevsk factory stock cartouches.
On the left - 1918-1928 type, in the middle - 1928-1937 type, on the right - 1937 and later.
Tula factory (1940 and earlier period) barrel shank markings.
Like the markings of the Izhevsk factory, Tula markings also have some variety. The fletching of the arrow has 5 lines on each side during all periods.
Wartime Tula factory #536 NKV (1942-1944) barrel shank markings.
Fletching of the arrow has 4 lines on each side.
Tula factory stock cartouches.
On the left - 1918-1928 type, in the middle - 1928-1940 type, on the right - 1942-1944 period.
One of the first markings was stamped on the barrel after it passed through a black powder pressure test. The main goal of the black powder pressure test was to find hidden defects inside the steel structure, it provided very high pressure, which showed hidden defects. When the barrels were tested, they were barrel blanks and not finished barrels. During further machining, the powder test marking, which was a "П in a circle", was machined off, and stamped again after barrel machining was complete. Izhevsk black powder test markings are bigger, Tula markings are much smaller. Both factories stamped it on the front left/mid part of the barrel shank.
In mid 1940 the obsolete black powder pressure test was replaced with a test using a VD high pressure cartridge (which provided approx. 420 MPa pressure). At this time, the Tula factory already stopped M91/30 production (in 1942 it was restrored at another factory, more details in "Manufacturers and production numbers" section) while Izhevsk replaced "П in circle" black powder test marking with a "Y in circle" marking.
At first the marking was quite small compared to the older "П in circle", sometimes it was stamped at the bottom of the barrel shank. Towards the end of 1941 the size became much bigger, at this time it normally was stamped on the top of the barrel shank.
When the newly created factory #536 in Tula started production in 1942 they continued to use the prewar pattern "П in circle" marking, but in fact, the rifles were tested using the VD cartridge.
On the left - Izhevsk bigger size "П in circle" marking, on the right - smaller Tula marking
On the left - early VD cartridge test "Y in circle" marking, in the middle - marking stamped on the bottom of the barrel shank, on the right - 1941 and later bigger size marking
Assembled rifles passed through two further tests. One of them was a test with two strengthened cartridges (324 MPa pressure). The difference from the black powder/VD cartridge test (which was only related to barrel strength), was that the "O in circle test" was supposed to check how well the bolt group interacts with the receiver. If a rifle successfully passed it, it was stamped with an "O in circle" marking on the front right side of the barrel shank. The other was an accuracy test, after which the rifle was stamped with "K in circle" marking in the same area.*
* Accuracy test shooting done at factories was different from the way it was done during field tests. Rifles were tested at shorter distances because factories did not used 100 meter shooting ranges. During field tests, shooting was done at a 100 meter distance, with the rear sight set to 300 meters. The 4 shot group (or 3 best shots) should be within a 15 cm circle (about 5.16 MOA) (during late 1930's and wartime years - 18 cm (6.19 MOA), with center of the group 17 cm higher than sighting point.
Only light ball ammo was used for accuracy tests, rear sight settings were counted also for light ball ammo.
"O in circle" pressure test and "K in circle" accuracy test markings. Photo courtesy of Ryan Ellott.
The test with two strengthened cartridges was introduced in 1922 (the earlier period will require further, more detailed research). Tested rifles were marked with a "OO" marking, these markings were only used by Izhevsk. The Tula factory did not use that marking and did not have its own. The OO marking was replaced with an "O in circle marking" in very early 1930's. This version of the marking was used by both factories. The change of the marking type occurred in the 1930's, however, some Izhevsk wartime rifles still have the older style "OO" marking instead of the newer "O in circle", likely because of the absence of the correct stamp.
Some rifles and carbines are missing the "O in circle" and "K in circle" markings (in case of Izhevsk issued specimens they are also missing military representative acceptance marking on the left side of the barrel shank). This clearly indicates that rifle was not tested at the factory, and that the barrel and receiver, when they left the factory, were not a part of the complete rifle. They were replacement barreled receivers with attached rear and front sights, that were shipped to army repair depots. In case of an urgent need they could be quickly assembled to a complete rifle configuration. These barreled receivers had atypical serial numbers (to a particular factory/year), because quite often they were numbered by repair depots. 1941-1942 Izhevsk barreled receivers were numbered by the Izhevsk factory, but they had their own serial number range, different from range that was used for regular rifles - letter number prefixes, typical to the complete rifles, were not used during their numbering .
1941 Izhevsk factory issued barreled receiver, currently part of a complete rifle.
"O in circle" and "K in circle" markings are missing, serial number range is atypical for 1941 (letter prefix is missing). "П in oval" black powder test marking is used instead of VD cartridge test typical for that period.
Photo courtesy of Tom Messimer.
Each part of the rifle, and the assembled rifle itself, passed through multiply quality control inspections. According to drawings/production standards, some parts were stamped with quality control department markings, some were not because of their small size, but all parts were inspected.
*For example, quality control markings on bayonets were on the side opposite to where the stamped factory marking was. On bolts, the location was near the beginning of the bolt handle, also on the opposite to the side where a factory marking was stamped. On the bolt cocking piece , they were on the rear side of the cocking knob, and so on.
Each factory quality control department worker (including the chief of the quality control department) had their personal marking. Until 1937 the quality control department was accountable to the general administration of the weapon factories, and not to the factory director. In 1937 it became a part of the factory structure. Quality control markings at both factories are quite varied and were different in different production years. In 1935-1936 production processes were modified according to requirements of the letter "B" drawings (optimized for mass production), this caused a big number of changes, including changes in markings.
Post 1935 rifles have a much bigger quantity of different inspection and operational markings that are visible on metal parts and stocks, earlier rifles don't have as many quality control markings. Izhevsk pre-1935 quality control proof marks look like a single letter or number, later ones look like different figures with number or letters inside. Tula pre-1932 quality control marking look similar to Izhevsk - single letter or number, 1932 and later markings - combination of the T and K letters in circle (OTK, abbreviation for Quality control department). Sometimes the Г letter was added (ГТК, Г means "Главк", "Chief department").
Samples of Izhevsk factory quality control proof marks.
On the left - pre 1935/1936 single letter/number marking, the others are markings that were used after the implementation of letter "B" drawings into production
* - letter or number
x- was used in 1945-1948, only on stocks
Samples of Tula factory quality control proof marks.
On the left - pre 1934 single letter/number marking, the rest are 1934 and later proofmarks. The far right image is a factory #536 NKV 1942-1944 proofmark.
* - letter or number
Samples of Tula factory quality control proof marks on the stock.
ОТК letters in a circle - quality control department marking (stamped twice). Ш in diamond - personal marking of the quality department chief, this was stamped since at least 1938 (later, in 1938-1940, an H in a diamond was used). During 1936-1937 a single letter without a diamond was used.
Poorly stamped letters in circle - "МП" initials, military representative personal marking, this will be covered in detail below.
Receivers and barrels were made from steel with a specific composition. These parts were supposed to hold high pressure, that's why it was very important to use steel manufactured according to strict specifications. Each steel lot that was used in production was assigned its own unique lot number. This lot number was stamped on both the barrels and receivers at least since 1930 (the earlier period will require more detailed research). The steel lot number on the receiver was stamped on the bottom flat part near the recoil lug. On barrels, initially it was stamped in the rear sight base area or further to the front sight area (on the bottom). In 1936, after the adoption of the letter "B" drawings, the location was supposed to be moved to the bottom of the barrel shank. However, this was done only by the Izhevsk factory, Tula continued to stamp steel lot numbers on barrels under the rear sight (up to 1940). 1942-1944 Tula barrels (barrels were primarily produced in Izhevsk) were stamped with steel lot number according to Izhevsk specs - on the bottom of the barrel shank. Sometimes the number was stamped offset and it was possible to see it over the wood of the stock. Steel lot markings consisted of letters and numbers, sometimes simple shapes, (2-5 symbols), stamped with larger font than all other markings, this made them easy to spot.
Despite the marking requirement set by the "B" drawings, receiver steel lot numbers were not stamped on Izhevsk wartime receivers.
Steel lot number on the barrel. # Box symbol 554
Location for: Izhevsk - pre 1935/1936 period, Tula - 1940 and earlier.
Steel lot number on the barrel. # 209
Location for : Izhevsk - post 1935/1936 period, Tula - 1942 -1944.
Steel lot number on the receiver. # ЧОФ67
The serial number is a combination of letters and numbers that was used as the main ID for a rifle during its service life. Serial numbers were stamped on the barrel shank, and with the same font, were also stamped on the bolt body, magazine floorplate and the stock buttplate. A factory matching rifle font should look the same on all parts (however because of the different angles of the application of the stamp, small visual differences are possible). There one exception to this rule - fonts used in 1942-1944 at the Tula factory #536 can look different on rifle and carbine parts. However, these differences are possible between few typical to factory font types, and they are different from the later postwar refurbishment fonts.
All rifles before 1938 had serial numbers consisting only of numbers, no letters. The serial number range (for M91/30's) was reset every year. In this system of numbering, the lower serial indicates earlier production of the firearm during calendar year and vice versa. In 1938 both Izhevsk and Tula factories switched to another system of numbering - consisting of a two letter prefix before the serial number. This system of numbering did not allow estimating (even roughly) a particular weapon's production period. The link between the production period to the letter prefix was established by special directives, issued by Main Artillery Directorate.
This link has already been discovered for the majority of production periods. Currently it will not be posted openly, it will be available only to subscribers of the site. Izhevsk switched to letter prefix serial numbers during the second quarter of 1938 (early 1938 Izhevsk rifles still had serial numbers without letter prefix), Tula switched on January 1st, 1938. Factory done serial numbers were always stamped during the final stage of assembly through bluing layer. This helps to verify if a particular rifle has the original bluing.
Until the end of the 1930's the serial number was stamped after rifles were accepted by a military representative. Later, after changes to the production instructions were introduced in 1939, serial numbers were stamped before rifles were provided for military acceptance. In case a rifle was rejected and returned for the rework, after which it was finally accepted, situations arose where rifles with earlier letter prefixes (meaning letter prefixes that were corresponding for the earlier months of production) were issued after rifles with later letter prefixes. These situations are very typical during wartime years of production.
Different styles of serial numbers.
On the left - pre 1938 serial number, on the right - 1938 and later serial number (with a letter prefix)
Sample of factory matching serial numbers. From the top to bottom - barrel, floorplate, bolt, buttplate.
Photo courtesy of Ryan Elliott.
On the top - rifle with factory original bluing, serial number is stamped over bluing. On the bottom - reblued rifle. Photo courtesy of Ryan Elliott.
2. Operational markings and proofmarks. Quality control markings were explained in the previous section. A rifle's parts, before they were inspected by quality control inspectors, were machined, assembled and adjusted by factory workers. These workers also had their own personal markings, completion of some production operations were also stamped on certain rifle parts. This was done so that quality control department workers and military representatives were able to find out who was responsible for a defective part or incorrect assembly. The majority of those operational proof marks had no sense and meaning in a short scale production period and are senseless for future research.
Each factory had their own locations for the majority of operational markings, they were not the same. However, there are at least a few markings that can provide additional information even today. Those markings are O and П letters in a circle (but not those that are stamped on the barrel shank), these markings mean "Опробовано" (tested) and "Пресс" (pressure). They mean that a rifle part was tested using devices administrating pressure or flexibility tests. Not all parts were tested, so not many of them had such markings. Commonly these marks can be seen on bolt heads, receivers, bayonets. П in circle is a relatively earlier mark than O in circle, which was adopted according to the letter "B" drawings and should replace П markings. Sometimes it can be seen on later guns, it was even used on 1944 Izhevsk receivers.
Typical operational proof marks on a 1934 receiver. Before quality control markings were changed in 1934-1936, operational markings and quality control markings had the same style - single number or letter.
On the left - pressure test marking on the receiver, on the right - test marking on a bayonet (previously a П in circle marking was used)
1 in circle marking - personal marking of the shooter who was responsible for the accuracy test. This was used since mid 1943 at the Izhevsk factory instead of paper cards, which were used earlier. The stock comb was a typical area for these markings, during the postwar refurbishment process similar markings were placed there.
Photo courtesy of Matt Darnell
ИЛ marking - initials of the worker who was responsible for assembly and adjustment of the barreled receiver and stock. This location for these kind of markings was used in the late 1930's by Izhevsk.
Photo courtesy of Ryan Elliott.
3.Markings about specific rifle/carbine configuration. Not all rifles and carbines issued by factories were just standard firearms produced with accepted drawings and technology. Some of them had difference in the tolerances, production technology and so on. These rifles (and parts) were marked with special markings.
One of the most common markings, used by both factories, was the "Д in circle" tolerance marking. It was used on rifles/parts that had non-critical deviations from the established drawings, but were accepted after a special directive of the military representative.
"Д in circle" tolerance marking
One of the most famous markings of this kind is the so called "sniper" marking. But these markings do not indicate a complete sniper rifle (which obviously looks different from a regular rifle), they are related only to the barrel, which was produced with higher accuracy than for a regular rifle. Not all barrels with such markings were used on sniper rifles, it is possible to see regular rifles with sniper grade barrels without mounts and scopes in standard 91/30 configuration
The Tula factory started to use specific marking for sniper grade barrels in 1934. It was a combination of СП letters, they were stamped above the factory star marking on the barrel shank. In 1942, when production of sniper rifles started at factory #536 in Tula, the СП letters were replaced by CH letters,. These CH letters can be seen in two sizes - smaller and bigger (smaller size is typical for 1944). The location of the stamping remained the same, but quite often this marking was stamped poorly. Barrels were stamped with "sniper" marking before first shot was made from them, marking indicates only higher accuracy during production. More details will be provided in sniper section.
The Izhevsk factory used another marking - capital C in a circle, which was stamped on the front part of the barrel shank. In 1942 and early 1943 it was stamped on the left side, later - on the right side. As mentioned previously, these markings can often be observed on regular rifles and even carbines. In 1942-1943 Izhevsk supplied many barrels to Tula, it possible to see barrels with double sniper grade markings - initially barrels were marked in Izhevsk, later in Tula.
Sniper grade barrel proof marks
On the left - prewar Tula marking, in the middle - smaller and bigger factory #536 Tula marking, on the right - 1942 and later Izhevsk marking.
There exist a number of proof marks, that definitely represent the same idea (something different about the construction compared to a regular rifle), but which exact meaning is unknown. So far none of the documents about their designation have been found.
Unknown Tula factory markings (1935-1940)
All factories always produced a certain quantity of training rifles. These rifles were mainly produced from defective parts, they were not functional - it was not possible to fire them. Such rifles were marked with "УЧ"letters ( "Учебная" , Training) on the barrel shank and possibly on some other parts as well (depending on the factory/period). Factories rarely produced the so called training-fighting rifles (учебно-боевые). These rifles were also produced from defective parts, but they were able to shoot. However, it was prohibited to use them in real combat at the front line. Good example where they were used: In 1943 a batch of these rifles was sent to guards at the optical factory in Yoshkar-Ola, which produced PU scopes. Training-fighting rifles were marked with УЧ-Б letters. Both types of these rifles can be factory issued or repair depot reworks converted from non serviceable rifles.
Factory issued training rifles
On the left - marking on a Tula M44 carbine (courtesy of James Minardi) , in the middle - Izhevsk issued rifle, on the right - training-fighting rifle (courtesy of Dave Phillips)
An interesting marking, the meaning of which was only recently discovered, is the CK marking that can be seen on some 1945 Izhevsk M91/30's. It means that a rifle with such a marking was initially a bullet velocity test rifle, and was produced with higher tolerance (with half decreased allowed deviations in parts sizes during production). These rifles were used at ammunition factories. These rifles and carbines were definitely produced in earlier periods (there are documents about their production in 1944 and the prewar period, by the Tula factory as well). However, these marking have only been observed on 1945 dated rifles. There are rifles and carbines marked with another marking (they were for sure) but they still need to be discovered.
Initial bullet velocity test rifle CK marking.
Photo courtesy of Nick Lord.
Many Izhevsk produced carbines and rifles (especially those produced in 1941) have a visible T in an oval marking. It can also be found on later firearms, sometimes without oval, sometimes on the barrel shank, sometimes on the stock. A T without oval can rarely be seen on prewar Tula riles (barrel shank area), smaller version of the T in oval marking have also been observed in rare cases on prewar Izhevsk rifles. It is highly probable that this marking indicates that rifle had a barrel with button made rifling (not cut rifling). At the moment documents that verify this for sure have not been discovered.
Button rifling technology made production of the barrels much faster, up to 10 times. It was introduced in small scale into production in 1938 (trials were made even earlier then that, since 1930), it was unclear how long the service life and durability of such rifles will be, so they required a special marking. In 1941 Izhevsk switched to mass production of barrels with button rifling (mainly for carbines), so in 1941 made carbines this marking is very common. Later, more and more rifles and carbines were issued with button rifled barrels, they showed good performance, and they were not stamped as much as earlier. However, these markings can be seen until late 1943, they were likely eliminated later. Towards the end of 1943, the majority of barrels already were being produced with button rifling, but a small quantity of them still had cut rifling. All barrels that were produced in 1942-1944 in Tula also had cut rifling.
Different styles of the T in oval / T proofmark.
Up to the mid 1930's, rifles that were in service and required overhaul were repaired by the factories. Later this was done by repair depots of the Main Artillery Directorate. According to the existing instructions, it was prohibited to disassemble the barrel and receiver, all rifles that required barrel replacement were sent to the factories. In the Russian/Soviet system, the barrel is the rifle, so rifles that got a new barrel (they were numbered within the range of the serial numbers used by particular factory during that year) also got parts with the same serial numbers (they were renumbered older parts or new parts).
In addition to the overhaul of used rifles, factories used some recycled parts in production. Use of recycled receivers is widely known, but other parts were reused as well. It will be correct to call this category of rifles "rifles built with use of recycled parts". Izhevsk marked these rifles with a <p> marking on the barrel (front right side of the barrel shank), and before the serial number on other numbered parts (bolt, floorplate, buttplate). This marking was used in 1923-1933, before that a P marking without <> was used (sometimes the P marking can be found on some parts in 1923-1933). After 1933 the use of recycled parts was stopped up until 1941-1942. Wartime rifles/carbines built with use of the recycled part did not had any special markings. The Tula factory used only the P marking on the barrel, it was not stamped near serial number on other parts.
Markings of an Izhevsk rifle built with use of the recycled parts. 1923 and later
Photo courtesy of Matt Darnell.
P marking on an Izhevsk rifle built with use of recycled parts. Pre 1923 period
Marking on a Tula rifle built with use of recycled parts
Factories always produced large numbers of replacement parts (and stocks also), which were used by repair depots and field armourers during a rifles maintenance, repair and refurbishment. Parts that required serial numbers at assembly , were issued unnumbered. Generally, all these replacement parts were marked with the letter "H" . If a part of your rifle has an "H" proofmark, it was originally issued as spare part.
"H" replacement part marking on various rifle parts
Military representative markings
All production processes during firearm production at the factories were controlled by military representatives. Military representatives were serviceman of the Main Artillery Directorate, they acted as an authority that ordered firearms from factories. Military representatives controlled quality of the produced firearms/parts.
There were two types of the military representative acceptance markings:
- final acceptance, this was stamped after a rifle was assembled and adjusted by the factory (and accepted by factory quality control), was then submitted for final inspection and passed it;
- operational markings that were stamped during production. These kinds of markings were a personal marking of the military representative office employee.
While final acceptance markings are well-known, operational markings still require further research. At the moment it is clear that they are quite similar to the factory workers personal markings and look like single letters or numbers, possibly in figures. Final acceptance markings from to the post 1930 period will be described below, the pre 1930 period will require its own description because those markings were very varied.
According to 1930 M91 production standard, the final military representative acceptance marking was stamped in two locations - on the front left side of the barrel shank, above the wood line, and on the right side of the buttstock, near the factory emblem. The same placement of the markings is mentioned in later instructions. It is interesting to note that before 1943, these markings were stamped this way only on Izhevsk rifles/carbines, Tula rifles had stamps only on stocks. In 1943 Izhevsk eliminated stamping on the barrel shank (early 1943 rifles still had them).
Most final acceptance marking were "two letters in a figure", a circle was often used, however, some difference were possible. Letters used in the markings were the initials of the chief military representative or the person who was responsible for a rifle's acceptance (depending on the period). If this person changed, the marking was changed as well. The owners of the majority of these initials used in the acceptance markings have already been identified, but this information will be provided in the subscriber section.
"ГВ in circle" military repsentative final acceptance marking.
1938 Izhevsk M91/30, photo courtesy of Ryan Elliott. ГВ letters are initials of chied military representative Г.Вауллин (G.Vaullin).
"ИЛ in rectangular" military repsentative final acceptance marking.
1939 Tula M91/30, photo courtesy of Ryan Elliott. ИЛ letters are initials of chied military representative И.Литичевский (I.Litichevskiy).
Izhevsk factory military representative final acceptance markings and periods when they were used
Tula factory military representative final acceptance markings and periods when they were used
