The Grille (German for “Cricket”) was a German self-propelled infantry gun used during World War II, based on the chassis of the Panzerkampfwagen 38(t) light tank and armed with a 15 cm sIG 33 heavy infantry gun. Its full official designation was schweres Infanteriegeschütz 33/1 (Sf) auf PzKpfw 38(t) Ausf. M “Grille” (Sd.Kfz. 138/1). The vehicle was produced in two main variants: the Ausf. H, introduced in 1943 with 91 units built using the rear-engine Panzer 38(t) Ausf. H chassis, and the improved Ausf. M, produced from 1943 to 1944 on the mid-engine Ausf. M chassis for better vehicle balance, resulting in 282 combat units and 120 unarmed ammunition carriers.
