The M142 High Mobility Artillery Rocket System (HIMARS) is a U.S. light multiple rocket launcher mounted on a standard Army Medium Tactical Vehicle (MTV) truck frame. The HIMARS carries six rockets or one Army Tactical Missile System (ATACMS) missile on the U.S. Army's new Family of Medium Tactical Vehicles (FMTV) five-ton truck, and can launch the entire Multiple Launch Rocket System Family of Munitions (MFOM). HIMARS is interchangeable with the MLRS M270A1, carrying half the rocket load.