I say old boy, is that a Type 94?
The British Army in Burma 1945: Soldiers examine a captured Japanese 37mm Type 94 anti-tank gun, January 1945. A U.S.-marked Bren carrier fitted with deep wading screens passes by in the background.
Per TM-E 30-480: Handbook on Japanese Military Forces, Technical Manual, U.S. War Department, October 1, 1944, via Lone Sentry:
Model 94 (1934) 37-mm gun. (1) General description. This weapon (fig. 212) is referred to by the Japanese as the “Infantry rapid fire gun.” It is an infantry close support weapon firing both high explosive and armor piercing high explosive ammunition. It has a semiautomatic, horizontal, sliding type breechblock. When the shell is loaded, the rear of the cartridge case trips a catch that closes the breechblock. Recoil action of firing opens the breech and extracts the cartridge case. Sighting is by a straight telescopic sight. This weapon has marked on the barrel the following [94 model 37-mm gun] which reads “94 model 37-mm gun.”
Characteristics.Caliber 37-mm (1.46 inch).
Length (over-all in traveling position) 114 inches.
Width (over-all in traveling position) 47 inches.
Weight 714 pounds.
Traverse 1,062 mils (60°).
Elevation +480 mils (27°).
Maximum range 5,000 yards.
Muzzle velocity (armor piercing ammunition) 2,300 feet per second.