Raupenschlepper Ost (RSO) - tracked tractor-East, a fully tracked, lightweight vehicle, in response to the poor performance of wheeled and half-tracked vehicles in the mud and snow during 1941 autumn and winter on the Soviet Front.
powered by a Steyr V8 petrol engine of 3.5 l giving 85 PS (63 kW)
3 versions: RSO/01; RSO/02; RSO/03 - cab material difference + wooden cargo bed
Pak 40 - Panzerabwehrkanone 40 - 75 mm anti-tank gun