 The Bayern @-@ class ships were protected with Krupp cemented steel armor , as was the standard for German warships of the period . They had an armor belt that was 350 mm ( 14 in ) thick in the central citadel of the ship , where the most important parts of the ship were located . This included the ammunition magazines and the machinery spaces . The belt was reduced in less critical areas , to 200 mm ( 7 @.@ 9 in ) forward and 170 mm ( 6 @.@ 7 in ) aft . The bow and stern were not protected by armor at all . A 50 mm ( 2 @.@ 0 in ) -thick torpedo bulkhead ran the length of the hull , several meters behind the main belt . The main armored deck was 60 mm ( 2 @.@ 4 in ) thick in most places , though the thickness of the sections that covered the more important areas of the ship was increased to 100 mm ( 3 @.@ 9 in ) . 
