The Heer panzer crew special uniforms were made as from 1934 onwards; a double breasted tunic , of a black coloured material . In the beginning this jacket ( wrapper) was only allowed to be worn when the crew was with the tank or armored vehicle, including half tracks. Away from the vehicle they had to wear the grey-green service dress uniform. This changed by the end of 1940 when the service dress uniform was no longer issued to the tank crews.
Crews of SS assault guns and tank detroyer units were equiped with the same wrapper design but made from stocks of grey-green wool.The drill uniform of the Waffen SS was the same. Towards the end of the war panzer and assault gun crews were wearing whatever they could lay their hands on
Hope this answers your questions and is of some help
guy