The M203 is a single-shot 40mm grenade launcher designed to attach under the M16 and M4 series rifles. Provides organic indirect fire capability at the squad level. Used in Vietnam through present day, firing HE, smoke, illumination, and less-lethal rounds. Type: Grenade Launcher Action: Single-Shot Caliber: 40x46mm SR Capacity: 1 Year introduced: 1969, USA Weight: 3 oz Overall length: 15" Status: Active Military use: Yes Intended use: Military, Squad Support