Development of the sIG 33 PzKpfw 38(t) started in late 1942.2
Some of the early models were converted when they came back to the factory for work.2 The sIG 33 gun was mounted on the body with an armored shield built around it.2 The engine area was covered so it could store ammunition.2
Production: April 1943 - June 1943, October 1943 - September 19441
sIG 33(SF) auf PzKpfw 38(t) Ausf M:
Production: 1942 - 19445
15cm sIG 33(SF) auf PzKpfw 38(t) Ausf H, SdKfz 138/1: Used Czechoslovakian 38(t) Ausf H chassis and was converted by Alkett. Engine was mounted in rear to expedite production.2,4 The fighting compartment was extended over the engine.
In June 1944, there were 12 issued (6 each) to the 38th Panzer schwere Infanteriegeschütz Abteilung of the 2nd Panzer Division.
15cm sIG 33/1(SF) auf PzKpfw 38(t) Ausf K, SdKfz 138/1: Produced by Böhmisch-Mährisch. The engine was mounted in the front and the gun towards the rear.2,3,4,5 Maximum range 4,700 meters. Used FuG16 radio.1
The gun fired a 83.8 lb HE shell at a muzzle velocity of 787'/sec. to a range of 5,140 yards.3