Type Time-fused grenade
Place of origin United States
In service 1918-1960s
Used by United States, Israel, Italy, Turkey, The Netherlands, Argentina, Chile
Wars World War I, World War II
Weight 1 lb 5 oz
Filling TNT or EC blank fire powder
Filling weight 2 oz
mechanism Timed Friction Fuse
The Mk 2 grenade is a fragmentation hand grenade (sometimes written Mk II) used by the U.S. armed forces during World War II and in later conflicts including the Vietnam War. It was phased out gradually, the U.S. Navy being the last users. It was generally replaced by the M67 and M61 grenades .
The Mk 2 was commonly known as a "pineapple" grenade, because of its distinctive shape. Grooves were cast into the cast iron shell to aid in gripping the grenade—this provision gave it the appearance of a pineapple fruit. A common misconception is that the grooves aided fragmentation of the grenade, which they do not. Although TNT was used as a filling, EC blank fire (smokeless firearm) powder was also used instead in some models due to the tendency of TNT to over-fragment the cast iron body. EC powder produced an adequate amount of fragmentation and did away with the need of a detonator. The detonator was initially replaced by a small length of safety fuse terminated with a black powder igniter charge. Production grenades with the EC powder filler used the M10 series of igniting fuse. It was also commonly referred to as the "frag".
* Grenade, Hand, Fragmentation, Mk II: EC blank powder filler, uses M10 or M10A1 igniting fuse.
* Grenade, Hand, Fragmentation, Mk IIA1: EC blank powder filler, uses M10A2 igniting fuse.
* Grenade, Hand, Fragmentation, HE, Mk II: TNT filler, uses M5 detonating fuse.
* Grenade, Hand, TNT, Fragmentation, Mk II: TNT filler, uses M6A4C detonating fuse.
* Fuse: Dependent on variant, includes M5 and M6 detonating fuses, and M10 igniting fuses. Later model fuses could also be fitted.