The fifth Ajax had moved on from the previous ones and was now an iron-clad battleship, albeit smaller and cheaper than earlier iron-clad ones, including 12.5” calibre guns rather than 16”.
She was launched on 10 March 1880 at Pembroke and commissioned 30 April 1885 into the Special Service Squadron Command; thereafter she was posted as guardship, then reduced to Reserve and further reduced to Fleet Reserve in 1893. In 1901 she was posted to Dockyard Reserve before being sold and broken up in 1904. 8510 tones; length 300 ft; Beam 66 ft. Two-shaft 6000hp engines. Crew compliment 345. Armament: 4x 12.5” muzzle-loading rifles; 2x 6” guns. Armour – up to 18” thick