The Royal Ordnance L7 is the basic model of Britain's most successful tank gun. The L7 was a 105 mm L/52 rifled design intended for use in armoured fighting vehicles. It was so successful that it armed not only British post-war designs, but was used almost universally in "the West" as the main armament of almost every main battle tank of the period.
The L7 was developed by Britain's Royal Ordnance Factories to equip British tanks of the postwar (Cold War) period as the successor to the 20 pounder (84 mm) used on Britain's postwar tankthe Centurion.
The L7 was a popular weapon and it was maintained in use even after it was superseded by the L11 series 120 mm rifled tank gun, for some Centurion tanks operating as Artillery Forward Observation and Armoured Vehicle, Royal Engineers (AVRE) vehicles. The L7, and adaptations of it, can be found today as standard or retrofitted equipment on a wide variety of tanks developed during the Cold War. It is also being used as the main armament of the U.S. Army's Stryker-based Mobile Gun System