The T48 57 mm Gun Motor Carriage was a self-propelled anti-tank gun produced by the Diamond T company in 1943 for the United States. The design incorporated a 57 mm gun M1, a US production of the British Ordnance QF 6 pounder, mounted on an M3 Half-track. The Soviets called it the SU-57 (Samokhodnaya ustanovka 57); under this designation it served in Operation Bagration and other fighting on the Eastern Front during World War II.