This is the concept. It uses a prototype 75mm cannon firing AP, HE, APHE, and APCR, with HEAT being tested. It features rugged suspension, good mobility, good firepower, and decent armor. It's powered by a 10.5L Diesel V12. The armor can hold up against 50. Cal and the turret can hold up against 37mm Cannons up front. Its pretty survivable. The prototype was designed in 1930, and a prototype was built in 1934. The tank is designed to enter service in 1938.