Complex sentence: The primary German assault gun was the Sturmgeschütz III (StuG III), but the Germans built a number of fully armored turretless assault guns, including the StuG IV, StuH 42, Brummbär, Sturmtiger.
Split into simpler sentences: The primary German assault gun was the Sturmgeschütz III (StuG III). The Germans also built a number of other fully armored turretless assault guns, including the StuG IV, StuH 42, Brummbär, Sturmtiger.