HERE is a very nice equipment plaque for a serialize navigation item from the company C.PLATH in HAMBURG a vet bring back.
If you google this name there is a very nice history and other threads showing equipment made by this company which still exists today under a new name. Unfortunately they do not talk about the REICH era. I suspect this company was heavily involved with compasses and gyros FOR THE V1 and V2 rocket projects

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PLATH.jpg (106.38 KB, 50 downloads)