The Rifle, Anti-Tank, .55in, Boys commonly known as the "Boys Anti-tank Rifle" (or incorrectly "Boyes"), was a British anti-tank rifle

Anti-tank rifle

An anti-tank rifle is a rifle designed to penetrate the armour of vehicles, particularly tanks. The usefulness of rifles for this purpose ran from the introduction of tanks in World War I and until the Korean War...

 in use during World War II

World War II

World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

.

There were three main versions of the Boys, an early model (Mark I) which had a circular muzzle brake

Muzzle brake

Muzzle brakes and recoil compensators are devices that are fitted to the muzzle of a firearm or cannon to redirect propellant gases with the effect of countering both recoil of the gun and unwanted rising of the barrel during rapid fire...

 and T shaped monopod

Monopod

A monopod, also called a unipod, is a single staff or pole used to help support cameras, video cameras, binoculars, rifles or other precision instruments in the field.-Camera and imaging use:...

, built primarily at BSA in England, a later model (Mk I*) built primarily at Jonathan Inglis in Toronto Canada, that had a square muzzle brake and a V shaped bipod

Bipod

A bipod is a support device that is similar to a tripod or monopod, but with two legs. It provides significant stability along two axes of motion .-Firearms:...

, and a third model made for airborne forces with a 30-inch (762 mm) barrel and no muzzle brake.