The 2.8 cm sPzB 41 (2.8 cm schwere Panzerbüchse 41, literally "Heavy antitank rifle") is a Nazi German anti-tank gun, which utilises the rarely used squeeze bore principle. The caliber of the gun is 28 mm at the chamber end and 20 mm at the muzzle. This construction allowed a muzzle velocity up to 1,400 m/s. The gun was designed and produced by Mauser-Werke AG. 2797 pieces were build from 1940 to 1943. In addition to the standard version, two more variants existed: the 2.8 cm sPzB 41 leFl 41 (2.8 cm schwere Panzerbüchse 41 auf leichter Feldlafette 41) which was developed for paratrooper units, and the 2.8 cm KwK 42 which was for tank mountings (only 24 of this version were produced, and it was never used in action).
