German WW2 Original Kreigsmarine Issue Wristwatch

Well documented example in the wonderful reference book ' A Concise Guide to Military Timepieces' by Z Wesolowski.Maker mark code ' 592' for the Alpina watch company. Along with 'KM' on the dial. Winds and tick over but no guarantee on working order longevity. Most likely needs a good service.No wristband.