The Sturminfanteriegeschütz 33B was an interim German assault gun built on the StuG III chassis to provide heavy direct-fire support against fortified enemy positions. Developed in response to the combat challenges of the Eastern Front, where standard 7.5 cm guns lacked the power to destroy concrete bunkers and unarmored 15 cm infantry guns suffered heavy losses, it combined a heavily armored, heightened superstructure with the 15 cm sIG 33 L/11 heavy infantry gun. Priority was placed on crew protection, though the added armor increased overall weight and reduced mobility. Produced rapidly in October 1942 as a stopgap measure until the dedicated Sturmpanzer IV Brummbär entered service, only 24 units were built. All were deployed to the Eastern Front, seeing intense combat during the Battle of Stalingrad with assault gun battalions and in subsequent attempts to relieve the encircled city. Only one Sturminfanteriegeschütz 33B survived the war and is currently on display at the Kubinka Tank Museum in Russia.
