The Boys Anti-Tank Rifle was adopted by the British military in 1937, and remained in production until 1943 when it was replaced by the PIAT. During that time more than 114,000 were made, both in the UK and in Canada. Canadian engineers at the John Inglis company devised a number of improvements to the rifle in 1942, which were adopted as the Mk I* pattern that year. Today we are looking at these improvements with examples of each type side by side. They are a new style of muzzle brake, simplified rear sight, and improved bipod design.