The H class was a series of battleship designs for the German Kriegsmarine, intended to fulfill the requirements of Plan Z in the late 1930s and early 1940s. The first variation, "H-39," called for six ships to be built, essentially as enlarged Bismarck-class battleships with 40.6 cm (16.0 in) guns. The "H-41" design improved the "H-39" ship with still larger main guns, with eight 42 cm (17 in) weapons. Two subsequent plans, "H-42" and "H-43", increased the main battery yet again, with 48 cm (19 in) pieces, and the enormous "H-44" design ultimately resulted with 50.8 cm (20.0 in) guns. The ships ranged in size from the "H-39", which was 277.8 m (911 ft 5 in) long on a displacement of 56,444 t (55,553 long tons), to the "H-44", at 345 m (1,131 ft 11 in) on a displacement of 131,000 t (129,0