Type 4 Ha-To

The Type 4 Ha-To (試製四式重迫撃砲 ハト, Shisei yon-shiki jū-hakugekihō hato) was a self-propelled gun developed by the Imperial Japanese Army for use in World War II.

The first prototype was completed in late 1944 and taken to the Imperial Japanese Army Academy for testing. Although testing indicated that it would be an effective weapon, it was expensive to produce, and the Japanese Army Technical Bureau shifted its attention to self-propelled multiple rocket launchers instead.

An additional three units were produced before the surrender of Japan, but none were used in combat.