The M79 grenade launcher is a single-shot, shoulder-fired, break open grenade launcher which fires a 40 x 46 mm grenade and first appeared during the Vietnam War. Because of its distinctive firing sound, it earned the nicknames of “Thumper”, “Thump-Gun” or “Blooper” among American soldiers; Australian units referred to it as the “Wombat Gun”. The M79 can fire a wide variety of 40 mm rounds, including explosive, anti-personnel, smoke, buckshot, flechette, and illumination. While largely replaced by the M203, the M79 has remained in service in many units worldwide in niche roles.