Kapt.z.S.

Captain at sea is a naval rank corresponding to command of a ship-of-the-line or capital ship.

The equivalent in other navies is ship-of-the-line captain or the naval rank of captain in the Commonwealth of Nations and the U.S. Navy.

Kapitän zur See (abbreviated KapzS or KZS) ("captain at sea") is the highest senior officer rank in the German Navy.

The official manner, according to ZDv 10/8, of formal addressing of military people with the rank Kapitän zur See is "Herr/Frau Kapitän zur See". However, in German naval tradition a Kapitän zur See will be addressed as "Herr/Frau Kapitän", or, often, in seamen´s language "Herr/Frau Kap'tän".

The rank insignia of a Kapitän zur See, worn on the sleeves and shoulders, is a five-pointed star above four stripes when worn on the sleeve. When worn as rank loops, typically on the shoulder, the star is omitted.

The rank is rated OF-5a in NATO, and is equivalent to Oberst in the Heer and Luftwaffe. It is grade A16 or B3 in the pay rules of the Federal Ministry of Defence and is senior to the OF-4 rank of Fregattenkapitän.

Kapitän zur See in the Volksmarine of the GDR was the highest grade of the senior officer´s rank group, comparable to NATO-rank code OF-5. The rank insignia consisted of shoulder strap and sleeve stripes. Shoulder straps had to be worn on uniform jackets and consisted of twisted silver braids with three gold pips on padding in a navy blue colour.

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