The No. 1 hand grenade was used by British and Commonwealth troops during World War One and was first introduced into service in July 1908. By the time it went out of service in mid 1917 it had advanced through three marks. The grenade pictured here is the No. 1 MkIII and has a brass body with segmented iron ring. The No. 1 grenade was fitted with fabric streamers to help it land head-first to allow the ‘Direct Action Percussion Fuse’ on top of the body to be struck, in turn, detonating the grenade.