The AT4 is a Swedish 84 mm (3.31 in) unguided, man-portable, disposable, shoulder-fired recoilless anti-tank weapon manufactured by Saab Bofors Dynamics. The AT4 is not a rocket launcher strictly speaking, because the explosive warhead is not propelled by a rocket motor. Rather, it is a smooth-bore recoilless gun. Saab has had considerable sales success with the AT4, making it one of the most common light anti-tank weapons in the world. The M136 AT4 and M136A1 AT4CS-RS are the variants used by the United States Army.