Comparing: Sturmpanzer I Bison vs. Wespe

Developed from 1939 through 1940 on the chassis of the Panzerkampfwagen I. Equipped with the 150 mm s.I.G. 33 gun that was mounted together with the gun carriage. Rate of fire was three rounds per minute; on-board ammunition totaled eight shells. The vehicle required the support of an ammunition carrier. The SPG was used from 1940 through 1943 during the French Campaign, Balkan Campaign, and on the Eastern Front. Later the Sturmpanzer II with a similar gun type was developed.

Self-propelled gun on the basis of the outdated Pz.Kpfw. II. The vehicle was designed as a mobile artillery unit for armored forces. The armored cabin with the modified 105 mm field howitzer was mounted on the middle and rear parts of the chassis. This SPG was a successful re-use of the outdated chassis. A total of 700 vehicles were built from 1943 through 1944.