Type 89 I-Go medium tank Type 91 6.5 mm machine guns. One was located in the front hull and the other placed in a turret ball mount pointed towards the rear, a practice followed with most Japanese tanks. The Type 90 57 mm tank gun had a barrel length of (L14.9) el angle of fire of −15 to +20 degrees, AZ angle of fire of 20 degrees, muzzle velocity of , and could penetrate of 20 mm of armor at 500 m (0.8 in/550 yd). Rather than using soft iron armor, as on the earlier Chi-I, the designers chose to use steel plate armor developed
Type 10 concluded that there was not enough internal space for a C4I system upgrade on existing tanks. Therefore, the development of a new main battle tank capable of various future battle missions was necessary. The use of modular components significantly improved the side armor compared to the Type 90. The Commander's Panoramic Sight was moved to the right and is located at a higher position than the Type 90, giving the commander a wide range of view. The vehicle's armor consists of modular sections, providing the ability to mount varying degrees of protection depending on the mission profile and weight requirements.