U-BOAT combat clasp in gold WWII German Kriegsmarine

U-BOAT combat clasp in gold WWII German Kriegsmarine, rare piece. A textbook example of a second war period Submarine Front Clasp ?U-Boot Frontspange?; in gold; the front with a central laurel wreath with a side profile of a submarine superimposed on the badge above two crossed swords, and witch six laurel leaves on either side of the wreath; horizontal tapered pinback with an integral hinge and a crimped round wire catch; maker marked ?Schwerin, Berlin? and designer marked ?Peekhaus? on the reverse