The Rifle No. 5 Mk I, nicknamed the "Jungle Carbine" for its use in jungle warfare, was a bolt action carbine derivative of the British Lee–Enfield No. 4 Mk I. It was developed per jungle fighting experiences in the Pacific War that led the British to decide "a rifle shorter and lighter" than the regular Lee–Enfield was critical for better mobility. Produced between March 1944 and December 1947, the Jungle Carbine was intended for and used in jungle environments where it gained its nickname. It notably saw widespread usage in on various sides of postwar colonial conflicts such as the Indonesian National Revolution, Malayan Emergency, and Vietnam War well into the 1960s, with sporadic use reported to have continued in several secessionist wars such as the Bangladesh Liberation War and Bougainville conflict throughout the rest of the 20th century.

A muzzle shroud, linear compensator, blast shield, forward blast diverter or concussion reduction device (CRD) is a sleeve that attaches to and extends beyond the muzzle of a firearm in order to redirect some of the noise and concussion, or shock wave, from the muzzle blast forward and away from the shooter, and other bystanders, behind and to the sides.