The BM-21 "Grad" is a self-propelled 122 mm multiple rocket launcher designed in the Soviet Union. The system and the M-21OF rocket were first developed in the early 1960s, and saw their first combat use in March 1969 during the Sino-Soviet border conflict. BM stands for Russian phrase боевая машина [Boyevaya mashina] (combat vehicle), and the nickname "Grad" means "hail".
In NATO countries, the complete system was initially known as the M1964. The M-21 field rocket system with a BM-21 launch vehicle (122 mm multiple rocket launcher (MRL) system) entered service with the Soviet Army in 1963. The launch vehicle consists of a Ural-375D 6×6 truck chassis fitted with a bank of rectangularly arranged 40 launch tubes that can be turned away from the unprotected cab.
