Pictured from my kriegsmarine collection is an emblem and a badge used by the Ubootwaffe as tradition cap insignia. The emblem for the National Socialist League of the Reich foe Physical Fitness( left) was worn as an U-Boat cap insignia by the crew of U-274, as was the Edelweiss gap device of the German Army Mountain Troops (right) by the crew of U-124. Examples of the these tradition badges are on page 77, page 81, and page 83 of 'Torpedo Los! THE FASCINATING WORLD OF U-BOAT COLLECTIBLES' by Gordon Williamson.
Pictured from my collection is a U-Boat tradition cap insignia 'Swordfish spearing an enemy sip' for the U-441 being worn by its Commander, Klaus Hartmann (white cap). All 51 hands, including Hartmann, died when U-441 was sunk by Allied depth-charges on 30 June 1944.