The Seehund (“Seal”) was the most effective of German midget submarines. The project XXVIIB was designed in spring 1944. Serial production was developed in Schichau Werk in Elbing and Germania Werft in Kiel. Up to the end of war there were built 285 units.

Since January 1945 they took active part in combat. Seehund midget submarines served in 312 K-Flottilla based in Ijmuiden (Holland). They accomplished 142 combat actions and sunk 9 Allied ships.

After the end of war 4 Seehund submarines served in French Navy up to 1956.