The Sturmgeschütz III (StuG III) assault gun was Germany's most produced armoured fighting vehicle during World War II. It was built on the chassis of the proven Panzer III tank, replacing the turret with a fixed superstructure mounting a more powerful gun. Initially intended as a mobile, armoured light gun for direct-fire support for infantry, the StuG III was continually modified.
- StuG III Ausf. C: (Sd.Kfz 142; April 1941, 50 produced) Gunner's forward view port above driver's visor was a shot trap and thus eliminated; instead, superstructure top was given an opening for gunner's periscope. Idler wheel was redesigned.
- StuG III Ausf. D: (Sd.Kfz 142; May–September 1941, 150 produced) Simply a contract extension on Ausf. C. On-board intercom installed, otherwise identical to Ausf. C.