Al is correct, that's a WWII German sailor, not an Imperial sailor.
The Imperial Navy rank and file wore the Reichskokarde, the Imperial cockade, on their caps, red-white-black. The Nazis implemented the eagle and swastika badge as the national emblem to be worn on headgear and uniforms. On headgear, the Reichskokarde was retained, as a symbol of the nation, while the eagle badge as added as a sign of "National Socialist spirit".
The corresponding badge for officers of the Imperial Navy consisted of the cockade, surrounded by a wreath of oak leaves, surmounted by Charlemagne's crown (the Germans claim his as Karl der Grosse, Charles the Great), which was chosen as a deliberate reference to the ancient Imperial authority of the German people. The Navy didn't use the state cockades, as the Army did, since the Navy was an Imperial instrument.
In the revived German armed forces, they retained the cockade, which was now the Bundeskokarde, the Federal cockade, red-gold-black, the old, old Imperial colors, and also, the colors adopted by the democracy movement in the 1840s, and again by the Republic after WWI.
Prost!
Brad