This piece of armour was designed by the body protection committee of the Medical Research Council early 1941. 5000 sets were tested positively by troops in the Middle East, and in April 1942 it was approved and put into production. Around 200,000 sets were produced but only 80,000 were issued: 65,000 to the RAF and 15,000 to the army. The majority of these were issued to the airborne forces.
The armour was made of 3 pieces of manganese steel of 1mm thickness. The backpanel protected liver, lungs and spinal column. The upper front panel protected the heart, aorta and lungs while the bottom front panel protected the wearer's belly.
Wartime manufacturers: Briggs Motor Bodies, Harrison Bros.& Howson (Sheffield).
Wartime variations: Initial sets had sorbo rubber fitted around the inside edges to keep the plates away from the body for ventilation. Rubber shortages forces led to a design were the plates were covered with webbing and the initial sorbo was replaced by felt pads.
Postwar modifications: A similar type of armour was used by the Belgian forces after the war. The rivets are put in from the other side compared to British examples and the webbing is light green instead of khaki..