The casemate battery was protected with of armour plate. Some of the main armament and armour plate was also removed. They lie directly below the large armour plate. Also, there remained the difficulty of applying armour plate to the hull. The first three were training shells that knocked splinters off the armour plate. Her deck was armoured with 3 inches (76.2mm) of armour plate. To allow for armour plate, these cars had developed De Dion rear suspension. An armour plate was welded over the hole. A piece of armour plate flew and killed a petty officer on "Liverpool". Grachev was impressed by the highly faceted armour plate on the Sd. Steel armour plate was the earliest type of armour. Behind this was another armour plate backed by of teak. As more armour plate was added in vital areas, crew members became less vulnerable.