90 mmgun M1/M2/M3 was an American heavy anti-aircraft and anti-tankgun, playing a role similar to the German 8.8cm Flak 18. It had a 3.5 in (90 mm) diameter
original M2, since it had the turret from the M3 Light Tank, with gun mantlet armor 2 inches (51 mm) thick. The M3 light tank was an upgrade of the M2 light
The M3gun motor carriage (M3 GMC) was a United States Army tank destroyer equipped with a 75mm M1897A4 gun, which was built by the Autocar Company during