Mk 2 grenade
| Mk 2 Grenade | |
|---|---|
| World War II–era Mk 2 grenade | |
| Type | Time-fused grenade | 
| Place of origin | United States | 
| Service history | |
| In service | 1918–1969 | 
| Used by | See Users | 
| Wars | |
| Production history | |
| Designed | 1918 | 
| Produced | 1918–1950s | 
| Specifications | |
| Mass | About 1 lb 5 oz (600 g) depending upon filling | 
| Length | 3.5 inches (89 mm) body 4.5 inches (110 mm) overall | 
| Diameter | 2.3 inches (58 mm) | 
| Filling | Varied | 
| Filling weight | Varied | 
| Detonation mechanism | percussion cap & time fuse: 4–5 second delay | 
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 2 April 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 The U.S. Navy was one of the last users of the Mk 2 when it was finally withdrawn from U.S. military service in 1969, replaced with the M33 series (M33/M67).