Mk IV helmet is a combat helmet that was used by the British Army in the 1950s to 1980s.[1]
It replaced the Mk III helmet and became the British Army's last metal helmet when it was replaced by the composite material Mk 6 helmet in 1985.
The Mark IV helmet was a modified design of the Mk III helmet with the chinstrap rivet moved down the bottom of the helmet shell as well as the introduction of a lift the dot style fastener for the inner liner.[2]