Ручная граната Mk 2: «Ананас» времён Второй мировой войны.

The Mk 2 grenade (initially known as the Mk II), also nicknamed the Pineapple is a fragmentation type anti personnel hand grenade introduced by the U. S. armed forces in 1918. It was the standard issue anti personnel grenade used during World War II, and also saw limited service in later conflicts, including the Korean War and Vietnam War. Replacing the failed Mk 1 grenade of 1917, it was standardized in 1920 as the Mk II, and redesignated the Mk 2 on April 2, 1945. The Mk 2 was gradually phased out of service as the M26 series (M26/M61/M57) grenade was introduced during the Korean War. Due to the tremendous quantity manufactured during World War II the Mk 2 was still in limited issue with the US Army and US Marine Corps throughout the 1950s and 1960s. The U. S. Navy was one of the last users of the Mk 2 when it was finally withdrawn from U. S. military service in 1969, replaced with the M33 series (M33/M67).

The Mk 2 grenade did not widely replace the failed Mk 1 grenade used by the U. S. military during World War I. Although 44 million were ordered and more than 21 million were completed (it was possible to convert Mk 1 grenade bodies to the Mk 2 configuration) before the war ended, few reached American troops overseas. It was formally standardized in 1920. The Mk 2, like the Mk 1, was manufactured of cast iron with a grooved surface divided into 40 knobs in five rows of eight columns. This was intended to enhance fragmentation (in practice, it was found that the grooves did not enhance fragmentation as much as desired) and provide a better grip when handling and throwing the grenade. The grooves and knobs gave it the appearance of a pineapple, and are the origin of the nickname. It was also commonly referred to as a "frag" grenade, in contrast to other types of grenades such as the Mk 3 concussion grenade also developed during World War I. The version of the MK2 in use around 1969, weighted 595 grams, had 57 grams of flaked TNT, and can be thrown at least 30 m (98). A 10 meter "effective causality" distance is listed, but this is likely a typo.) introduced in 1942 was filled through the fuse well instead. The Mk 2A1 was initially filled with of EC powder. In 1944, the EC powder filling was replaced with of TNT. Low explosive filled Mk 2s had their cast iron bodies painted gray or black to prevent rust. Pre WWII high explosive filled Mk 2s were painted bright yellow. During wartime (from about 1943 onwards), grenades were overpainted in olive drab, leaving a narrow yellow ring remaining at the top. Not all were overpainted, however, as D Day film footage shows. Mk 2 practice grenades were painted red (a practice copied from the French military). M21 practice grenades were painted light blue (a practice copied from the British military) and had blue painted fuse levers, often with the end painted light brown indicating a "low explosive" marking charge.

Gervasi, Tom. Arsenal of Democracy II: American Military Power in the 1980s and the Origins of the New Cold War: with a Survey of American Weapons and Arms Exports. New York: Grove Press, 1981. Rottman, Gordon. The Hand Grenade. Oxford: Osprey Publishing, 2015. War Department. Field Manual FM 23 30 1944: Hand and Rifle Grenades; Rocket, AT, HE, 2.36″ (February 1944); pp. 5–6.