The 9k37 buk is a mobile anti-aircraft and anti-missile defense system of soviet, and now russian, origin. The first prototypes of this system appeared in the late 1970s, and it entered service with the soviet army in 1979 or 1980. The basic guided missile of this system is estimated to be approximately 5. 5 meters long and weigh approximately 690 kilograms, with the warhead weighing around 70 kilograms