10.5cm leFH 18/40 auf Gw IVb Heuschrecke SdKfz 165/1 "grasshopper" at 18 tonnes was not exactly jumping around, but it had an interesting feature: the turret was de-mountable, making the turret into a movable pillbox. This was a prototype design in 1942, only eight were built before the project was terminated This grasshopper now sits in the field of the Aberdeen Proving Grounds.