The Type 1 Ho-Ni I was developed by utilizing the existing Type 97 chassis and engine, and replacing the gun turret with a Type 90 75 mm field gun mounted in an open casemate with frontal and side armour only, which made it very vulnerable in close combat. The mounting for the 75 mm Type 90 field gun allowed for 20 degrees of traverse to either side and -5 to +25 degrees of elevation. The plan was for self-propelled guns of the Ho-Ni series to form part of a fire support company in each of the tank regiments. Production of the Type 1 Ho-Ni I took place during 1942. It was first deployed in combat during the Battle of Luzon in the Philippines in 1945, but like the rest of the Japanese armor, they were defeated in action against superior US Army forces.