Crusader

Image: Cleaning the barrel of 6pdr main gun, Tunisia 1943

The Tank, Cruiser, Mk VI or A15 Crusader was one of the primary British cruiser tanks of the early part Second World War and perhaps the most important British tank of the North African Campaign. The Crusader's mobility made it a favourite of British tank crews and once upgraded with the Ordnance QF 6 pounder main gun made it more than a match for the early Panzer III and Panzer IV tanks it faced in combat. Retained in service because of delays with its replacement, by late 1942 the lack of armament upgrade combined with the presence of Tiger I Tanks among the Afrika Korps and reliability problems due to the harsh desert conditions, led to the Crusader being replaced in the main line of battle by US-supplied M3 Grant and Sherman medium tanks. The next British cruiser in combat would be the Cromwell heavy cruiser.
http://military.wikia.com/wiki/Crusader_tank