The M7 bayonet (NSN 1095-00-017-9701) is a bayonet that was used by the U.S. military for the M16 rifle, it can also be used with the M4 carbine as well as many other assault rifles, carbines and combat shotguns. It can be used as a fighting knife and utility tool. It was introduced in 1964, when the M16 rifle entered service during the Vietnam War.