Mk III Helmet

The Mk III Helmet was a steel military combat helmet developed for the British Army in 1941. First worn in combat by British and Canadian troops on D-Day, the Mk III was used alongside the Brodie helmet for the remainder of the Second World War. It is sometimes referred to as the "turtle" helmet by collectors, because of its vague resemblance to a turtle shell.

The Mark III helmet was designed to provide better protection for the side of the head than its predecessor. It was a deeper helmet with a smaller brim and provided 38% more protection than the Mark II, particularly at the sides. The Mark III helmet was issued primarily to assault troops for the Normandy invasion in June 1944, and a large number of helmets from British stocks were issued to the 3rd Canadian Infantry Division in addition to British units. Small numbers also went to the 2nd and 4th Canadian Divisions. All Mark III helmets in Canadian stores were returned to the UK shortly after the end of World War II.

The Mk III gradually replaced the Brodie helmet from 1944 onwards. The Mk III was replaced after the war by the Mark IV helmet, which it closely resembled. The differences were that the rivets attaching the chinstrap to the helmet were placed much lower down on the shell and the use of a "lift-the-dot" fastener for the liner. These modifications allowed the Mk IV to be utilised for carrying water. The Mark IV helmet was eventually replaced by the Mark V, which looked similar to the MK IV, but had a more padded liner. The Mark V was used until the late-1980s, whereupon the British replaced all steel helmets with the nylon fibre Mark 6.