Mark (designation)

Two Ford Mondeo sedans, a Mk II (grey, left) and a Mk III (blue, right)

The word mark, followed by number, is a method of designating a version of a product. It is often abbreviated as Mk or M. This use of the word possibly originates from the use of physical marks made to measure height or progress. Furthermore, by metonymy the word mark is used to note a defined level of development or a model number.

The kind of products that use this convention vary widely in complexity. The concept shares some similarities with the type designation (in hardware), also called software versioning : 1.0+ (1.1, 1.12, 2.0, 3.0, etc.), used to designate general software product releases, and other version control schemas. Thus designations like "Mark I", "Mark II", "Mark III", "Mark IV", etc. come to be used as proper names for persons and products.

Application

Mark refers to a mark on the modification plate of a system, component or machine. Modification plates are used to identify which modifications have already been applied to the device, either at the factory or by maintainers. The use of Mark as a method of versioning has entered common usage however, and may be applied to devices without a modification plate to physically mark.

United Kingdom

In British military practice, Mark ("Mk") designations were given in Roman numerals ^[1] (replaced by Arabic numerals in 1944 ^[2] ) to reflect variants of or production changes to service weaponry, either on their own or as part of numerical ("No.") designations; in the Lee-Enfield rifle series for example, the SMLE rifles were produced to Mk I, Mk III, and Mk V specification (with the latter two later gaining a numerical designation of "No. 1 Mk III/Mk V Rifle"), while the No .4 rifles were produced to No. 4 Mk I and No. 4 Mk 2 specification. Variations or production changes could be further denoted with an asterix ^[3] as with the SMLE Mk III* (later "No. 1 Mk III*") and No. 4 Mk I*. The British Army switched to Land Service number designations ("LXA1/A2/A3/etc.") in 1954, ^[4] but legacy items ^[a] continued to be referred to by their Mk designations until their replacement by newer equipment. ^[24] To this day, there are stores using an Mk designation that are still in service such as the No. 1 Mk 4 Protective Suit. ^[25]

British railway coaching stock has been referred to using Arabic numeral marks following the introduction of the British Railways Mark 1 in 1951, with further designs being referred to as the Mark 2 (introduced in 1964), the Mark 3 (introduced in 1975), and the Mark 4 (introduced in 1989). The Mark 5 designation was initially intended for coaches belonging to the 1990 InterCity 250 project, but this was cancelled in 1992; the designation was later applied to CAF-built coaches used on the Caledonian Sleeper service since 2019, replacing earlier Mark 2 and Mark 3 coaches, while coaches built by the same manufacturer for TransPennine Express are referred to as the Mark 5A.

United States Navy

The United States Navy uses the terms "Mark" and "Mod" as a method to uniquely designate specific types and configurations of equipment that would otherwise lack military designations. The practice was adopted by the Naval Ordnance group in 1944, and was formalized in the MIL-STD-1661 MARK and MOD Nomenclature System ^{[26] [27]} in 1978. As the system came from the Ordnance group, it is primarily used to describe naval guns, gun mounts, and other similar weapon systems.

Examples

Military

• Mark I, the first British Army tank design to see service
• Mk 2 grenade (an American grenade used in World War II, Korean War and the Vietnam War)
• Mark III, Merkava main battle tank (Israel Defense Forces)
• Mark 4 aerial atomic bomb, several United States atomic gravity bombs employed a Mark-# scheme (USAF)
• A.T. Mine G.S. Mark V an anti-tank mine of the WWII British Army
• Mk 6 Assault Boat (British Army)
• Mark 7 nuclear bomb
• Tank, Cruiser, Mk VIII - eighth in series of British Army cruiser tanks
• Mk 11 Sniper Weapon System (US Armed Forces)
• Mark 12 Mod X Special Purpose Rifle (US Special Operations Forces)
• Mk 13 missile launcher (anti-ship/anti-aircraft) (US Navy)
• Mark 14 Mod 0 Enhanced Battle Rifle (US Armed Forces)
• Mk 16 SCAR-L and Mk 17 SCAR-H assault rifle and battle rifle commissioned by the US armed forces
• Mk 18 CQBR M4A1 Receiver upgrade (US Armed Forces)
• Mk 19 grenade launcher (US Armed Forces)
• Mark 48 torpedo as well as other torpedoes used by the British and US Navies

Vehicles

VW Golf Mk III

• The AC Cars Cobra — MkI, MkII and MkIII
• The Ford GT40 series — MkI, MkII, MkIII and MkIV
• Various Jaguar Cars — Jaguar Mark 2, Jaguar Mark IV, Jaguar Mark X, etc.
• The Lincoln Mark series - Continental Mark II, Lincoln Mark VIII, etc.
• Various Lola Cars - Mk.4, Mk.5, Mk.6
• Various Toyota vehicles, especially the MR2 — MkI, MkII, MkIII
• Volkswagen Golf automobile — Mk1, Mk2, Mk3, Mk4, Mk5, Mk6, Mk7, Mk8
• British Rail Coaches — Mark 1, Mark 4, etc.
• The Walt Disney World Monorails - Mark IV and Mark VI.

Musical and photo instruments

• Rhodes piano — Mark I, Mark II
• Mesa Boogie Mark Series — guitar amplifiers, Mark I to Mark V
• Telharmonium, an early electronic musical instrument, Mark I to III
• SELMER Saxophones — Mark VI and Mark VII Series of saxophones
• Elektron music machines — Mk II versions of the Monomachine synthesizer and the Machinedrum drum machine
• Canon EOS-1D series — 1Ds Mk II, 1D Mk III, 1Ds Mk III, etc.

Firearms

Ruger Mk I at top; Ruger Mk II; Ruger Mk IV Hunter. demonstrates the use of the designation as the name, often referred to simply as "the Mk II", "a Mk III", etc.

• Ruger Standard series (Ruger MK I, Ruger MK II, Ruger MK III)
• Weatherby Mark V

Electronics

• Harvard Mark I, Mark II, Mark III, and Mark IV, early computers designed by Howard Aiken at Harvard University from 1937 to 1952
• Navigation system on BMW cars - Mk I, Mk II, Mk III and Mk IV

Medical research

• The term SARS‑CoV‑2 for the novel Coronavirus may be considered part of this designating method. The term COVID-19 has been misinterpreted in this way on several occasions; the number here, however, denotes the year of the first appearance of the virus, 2019.

See also

• British military aircraft designation systems
• Army Nomenclature System
• Mark I
• Mark II
• Mark III
• Mark IV
• Mark V
• Mark VI
• Mark VII
• Mark VIII
• Mark IX
• Mark X
• Mark XI
• Mark XII
• Mark XIII
• Mark XIV
• Mark XV
• Mark XVI
• Mark XVII
• Mark XVIII
• Mark XIX
• Model
• Type (designation)

Notes

1. Including but not limited to the No. 4 Rifle, ^[5] the various Sten machine carbines, ^[6] the original .303 versions of the Bren gun, ^[5] the No.5 Mk 1 Bayonet, ^[7] the No. 8 Mk 1 0.22in Rifle, ^{[8] [9] [10] [11]} the No. 36M Mk 1 HE Hand Grenade, ^[12] the No. 80 Mk 1 White Phosphorus Smoke Hand Grenade, ^{[13] [14] [15]} the No. 1 Mk 3 6 Inch Beehive Demolition Charge, ^{[16] [17] [18] [19] [20]} the No. 14 Mk 1 11 lb Hayrick Demolition Charge, ^{[21] [22]} and the No. 1 Mk 3 Pyrotechnic Pistol Signal Kit. ^[23]

References

1. Dunlap, Roy F. (1948). Ordnance Went Up Front. Small-Arms Technical Publishing Company. p. 139.
2. Clarizia, Vincenzo (11 August 2022). Ancient Weapons of Oman: Volume 2 - Firearms. Archaeopress Publishing Ltd in association with the Ministry of Heritage and Tourism. p. 98. ISBN   9781803270333.
3. Rottman, Gordon L. (2002). Korean War Order of Battle: United States, United Nations, and Communist Ground, Naval, and Air Forces, 1950-1953. Greenwood Publishing Group. p. 195. ISBN   0275978354.
4. Laidler, Peter; Edmiston, James; Howroyd, Davd (7 August 2020). A History of the Small Arms made by the Sterling Armament Company. Barnsley: Pen & Sword Military. pp. 86–87. ISBN   9781526773302.
5. Ministry of Defence (United Kingdom) (1982). Army Code No. 71295, Cadet Training Manual (CCF Army Sections).
6. WO Code No. 8948, Infantry Training Volume I, Pamphlet No. 4 The Sub-Machine Gun (All Arms) (Amended April 1957). War Office. 21 November 1955.
7. Laidler, Peter; Edmiston, James; Howroyd, David (7 August 2020). "Chapter Sixteen, Accessories and Ancillaries". A History of the Small Arms made by the Sterling Armament Company. Barnsley: Pen & Sword Military. pp. 286–290. ISBN   9781526773302.
8. War Office (1961). WO Code No. 13217, User Handbook for the Rifle, 0.22in., No. 8, Mk. 1.
9. Ministry of Defence (United Kingdom) (1970). Army Code No. 13217, User Handbook for the Rifle, 0.22in, No 8, Mk 1 and Rifle, Aiming, 0.22in L2A1.
10. "Armed Forces' Rifles". Parliamentary Debates (Hansard) . House of Lords. 30 March 2000.
11. Ministry of Defence (United Kingdom) (2005). Army Code No. 14233, The Army Cadet Force Manual.
12. WO Code No. 9941, Infantry Training Volume 1, Pamphlet No. 7 Grenades (All Arms). War Office. March 1964. pp. 1–8, 48.
13. WO Code No. 9941, Infantry Training Volume 1, Pamphlet No. 7 Grenades (All Arms). War Office. March 1964. pp. 18–23.
14. Ministry of Defence (United Kingdom) (May 1975). Army Code No. 71001, Infantry Training Volume III, Pamphlet No. 13 Grenades.
15. Army Code No. 71001, Infantry Training Volume III, Pamphlet No. 13 Grenades and Associated Weapons. Ministry of Defence (United Kingdom). October 1995.
16. "Sennybridge Range". Parliamentary Debates (Hansard) . House of Commons. 26 July 1993.
17. Mondial Defence Systems. "Beehive Charge Mk.6" (PDF). Archived from the original (PDF) on 2010-09-28. Retrieved 2020-06-12.
18. Chemring Energetics UK (February 2016). "Charge Demolition No.1 6 inch Beehive" (PDF). Archived from the original (PDF) on 19 June 2018. Retrieved 12 June 2020.
19. "Beehive Charge Demolition No 1 6in (sectioned)". Imperial War Museum . Retrieved 9 April 2022.
20. Chemring Energetics UK (October 2016). "A Leading Provider of Energetic Materials" (PDF). Retrieved 9 April 2022.
21. Mondial Defence Systems. "Charge Demolition No. 14 Mk 1" (PDF). Archived from the original (PDF) on 2014-01-23. Retrieved 2020-06-04.
22. Mondial Defence Systems. "Charge Demolition Necklace L1A1" (PDF). Archived from the original (PDF) on 2014-01-23. Retrieved 31 May 2020.
23. "Bullet Points" (PDF). Soldier Magazine . British Army. January 2012. p. 65. Retrieved 15 November 2025.
24. Gander, Terry (20 October 1986). Encyclopaedia of the Modern British Army (3rd ed.). Book Club Associates by arrangement with Patrick Stephens Limited. pp. 99–100. ISBN   085059684X.
25. "Smock, Protective NBC Suit, No.1, Mk. IV: British Army". Imperial War Museum . Retrieved 11 January 2026.
26. MIL-STD-1661 (1978-08-01). "Mark and Mod Nomenclature System" . Retrieved 2022-12-13.
27. "MIL-STD-1661 (OS) 1 August 1978 MARK and MOD Nomenclature System" (PDF). Defense Logistics Agency. 1 August 1978. Archived (PDF) from the original on 13 December 2022. Retrieved 12 December 2022.

External links

• Miscellaneous designation systems