Which concept that was similar to  Type 2 Ho-I was developed in the late  1930s?
Type 2 Ho-I:  Similar in concept to early variant of the German Panzer IV, it was designed as a self-propelled howitzer to provide the close-in fire support for standard Japanese medium tanks with additional firepower against enemy anti-tank fortifications. Panzer IV: The "Panzerkampfwagen" IV (PzKpfw IV), commonly known as the Panzer IV, was a German medium tank developed in the late 1930s and used extensively during the Second World War.
Panzer IV