The sIG 33 gun was installed on the base of tank Pz.Kpfw.38(t) by the firm VMM. In November 1943 the production of new tank hunter Sd.Kfz.138/1 was started. Its arms consist of 150mm sIG-33/1 gun. The thickness of front armor was equal 25mm. The ammunition supply consists of 18 rounds. In total 288 hunters were produced.