A new hull design was used that was similar to the PzKpfw III Ausf J and PzKpfw Ausf L hull. The side plates were extended past the front plat and holes drilled for towing brackets. The rear deck was extended and ventilation for the engine was improved. In 1942 Alkett ceased production on the PzKpfw IIIs and concentrated on the StuGs. As a result some of these were built on PzKpfw III hulls. These can be identified by the single piece forward opening hatch over the final drive.