A grenade launcher was a portable weapon used to shoot grenades over longer distances than they could normally be thrown.
Grenade launchers were military weapons that greatly improved the range of grenades. Grenades fired by grenade launchers always exploded on impact, regardless of timers. Grenade launchers were generally not able to hurl thermal detonators because these devices were too big and heavy, however some launchers such as the Thermal Detonator Launcher were specially made to fire these powerful explosives. Grenade launchers could also be mounted on a rifle, creating a dual-purpose weapon. The Under-barrel grenade launcher was one example of this.
The main variants of grenade launchers were the Micro-Grenade Launcher which fired smaller grenades and the Grenade mortar which lobbed grenades over distances longer than a kilometer. Other variant models of grenade launchers included the RD-4 grenade launcher, the TTT-54 "Thumper", the HH-4 grenade launcher, the Concussion grenade launcher, and the EMP Launcher.
Grenade launchers were also attached to a number of vehicles. Examples of vehicles with grenade launchers include the A5 Juggernaut, the Arrow-23 landspeeder, the All Terrain Personal Transport, and the All Terrain Scout Transport. The Galactic Empire's Merr-Sonn Mobile Grenade Mortar was the vehicle form of a grenade launcher. The Grenade Mortar could fire up to one hundred grenades per second. The Empire also sometimes equipped grenade launchers on a Mobile Defense Unit. Grenade launchers could also be mounted to starfighters, making it possible for some ships to fire concussion grenades. By adding these launchers, a starfighters overall effectiveness could be greatly raised.
During the Clone Wars, Clone jet troopers would use grenade launchers loaded with EMP grenades which were effective against droid adversaries. During the Rebellion era, Spacetroopers would use grenade launchers with a variety of grenades during their boarding missions.