Comparing: M3 Stuart vs. Cruiser Mk. II vs. T-127

Developed in 1938 through 1941 on the basis of the M2. Mass-produced from 1941. More than 13,000 vehicles in various versions were built, from the M3 to the M3A3, all of which were supplied to almost every allied nation under Lend-Lease. The M3 tanks were designated Stuart I by the British, while the M3A1 version received the designation Stuart III. The M3 first saw action in the battle at Sidi Rezegh.

The A10 Cruiser Mk. II was a further development of the A9 modification designed by John Carden. The A10 had enhanced armor and no machinegun turrets. A prototype was built in July 1937 and adopted for service as a heavy cruiser tank. A total of 175 vehicles were ordered between 1938–1939, which were manufactured by September 1940. The vehicles saw combat in France (1940), Greece (1941) and North Africa (1941).

Developed together with the T-126 at Factory No. 174 during the summer of 1940. Vehicle development was suspended during the preliminary design phase and then discontinued due to problems with the V-3 diesel engine.