The Buk is a family of self-propelled, medium-range surface-to-air missile systems developed by the Soviet Union and its successor state, the Russian Federation, and designed to counter cruise missiles, smart bombs, fixed- and rotary-wing aircraft, and unmanned aerial vehicles. In the Russian A2AD network, Buk is located between the S-200/300/400 systems above and the point defense Tor and Pantsir type systems below. The Buk-M1 uses the GM-569 chassis designed and produced by JSC Metrowagonmash. The crew compartment provides protection from small arms fire as well as being sealed against NBC attacks. The suspension on either side consists of six dual roadwheels with the drive sprocket at the rear, idler at the front, and four track-return rollers which support the inside of the double-pin track only. The 9K37 SA-11 Gadfly can run at a maximum speed of 65 km/h on a road and 45 km/h on cross-country, with a maximum range of 500 km.