Tank Modifications
Following the fighting which had taken place in 1939-1940, the Heer was in the process of increasing the armour thickness on all of its tank designs thus factories were producing tanks with increased armour thickness. However, for those tanks already in service, field modifications were made where armoured plates were bolted onto the tanks to bring them up to the new specifications.
The majority, but not all, of tanks from the 5. and 8. Panzer-Regiments shipped across to North Africa during Operation Sonnenblume had received these field modifications and a small number were from the new factory production run.
All tanks which were sent to North Africa were also modified for the tropical conditions, this included improving the engine air cooling circulation, the speed of the radiator fan increased and holes cut into hatch covers on the rear decks on the tanks.
Read more about this topic: Operation Sonnenblume