The german army (Heer) used black as their panzer uniform. This was function as well as fashion. Panzers are dirty. The fashion aspect, well...hats off to the German sense of what looks cool. The Heer were very proud of their black uniforms and the totenkopf (death's head)was a hold over from the cavalry regiments of the Hussars. Needless to say they were a little cheesed when the allgemeine SS (political arm) adopted their insignia and were using the black uniform. The Waffen SS (the military branch) also used the black panzer uniform but also took advantage of the issued and adopted (Italian) camo uniforms. Self propelled and assault gun crews used the feldgrau (field grey) uniform. BTW, Wehrmacht is the umbrella term for the national german forces made up of the Heer, Luftwaffe and Kriegsmarine (army, airforce and navy). The Waffen SS were the armed forces of the politcal branch or party.
THe waffenfarbe or shoulder piping was: rose for armored, brown for motorized recon,red for artillery, grass green for panzergrenadiers, white for infantry and a selected group of panzer grenadiers. The confusing part comes with the panzerjaeger units in that they were attached to other companies and often wore the piping of the parent company so theirs can be a mixed bag dependednt on who they are serving with.
As armornut pointed out American units used OD, with its varying shades. I'm not real familiar with the British or Soviet uniforms but I'm sure someone can help you.
Mike
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