High Quality Content by WIKIPEDIA articles! The Type 1 Chi-He (????? ??, Ichi-shiki chusensha?) was an improved version of the Type 97 Chi-Ha medium tanks of the Imperial Japanese Army in World War II. It had a more powerful main gun and engine and thicker armor.After the start of World War II, the Imperial Japanese Army quickly realized that its main battle tank, the Type 97 Chi-Ha, was inferior to contemporary Allied designs, such as the M4 Sherman or even the M3 Stuart. The Type 97?s low-velocity 57 mm main gun could not penetrate Allied armor, whereas its own thin armor made the Type 97 vulnerable in any combat against an adversary with even minimal anti-armor capabilities.