This is an exceptionally rare piece of insignia, as most female guards did not wear these due to scarcity.  That said, they were approved for wear and were produced.  This particular specimen was obtained by me from none other than Dave Delich.  I misplaced it years ago, and only now found it while doing a massive re-organization of my office.  Dave had two of these, and traded me his extra (he wanted only one of each specimen, and I was lucky enough to get this one).  You will notice in the photo of 3 guards from Auschwitz wearing them (attached to this listing), that there appear to be 3 different types even in this picture!  Strange, for such a rare piece of insignia, that there was such a variety!