The experience of civil war in Spain showed, that armor and armament of Panzer I were insufficient, and, therefore, the production was seized in 1939. Nevertheless, the chassis of Panzer I had been used for the purpose of self-propelled artillery. In January 1940 first 38 heavy field guns were installed on the chassis of Panzer IB. Tank turret and upper hull superstructure were removed and, instead, armor box-like shield, opened from above and behind was installed. The sIG-33 gun was mounted on its original wheeled lafette. Six companies of these spg were engaged in battles in Belgium and France, and, later, all over European battle theatre until 1943. Inspited the obvious overload of Panzer I chassis, Bison I spg proved to be quite reliable. Some of them remained on the front line in Russia until mid-1943. About 132 spg's of this type were produced. Later on the sIG-33 guns had been installed on the Pz38(t) chassis, which turned to be much more suitable for this purpose.
Technical Data
Length : 4,670 mm
Width : 2,060 mm
Height : 2,800 mm
Battle Weight : 8,500 kg
Speed : 40 km/h
Armament : 15cm sIG-33 I/11
Crew : 4
