The early Chi-Ha had a main armament of a 57mm gun and a 7.7mm secondary gun although following a 1939 clash with Russian tanks on the Mancguria-Mongolia border where the Russian guns outclassed the 57mm it was later replaced with a high-velocity 47mm in a new turret ("ShinHoTo") to produce the ShinHoTo Chi-Ha. The ShinHoTo Chi-Ha entered service in 1942 and was produced up to 1945. Crewed by four men the armour was thin at only 33mm.