2S7M Malka is a Soviet self-propelled 203 mm cannon. "2S7" is its GRAU designation. More than 250 units were built; some sources say 500, others up to 1,000. They were distributed around the former Soviet states during the dissolution of the Soviet Union in 1991. The 2S7 Pion was identified for the first time in 1975 in the Soviet Army and was called M-1975 by NATO (the 2S4 Tyulpan also received the M-1975 designation), whereas its official designation is SO-203 (2S7). It used a new-design chassis, partly based on T-72 and T-80 design, carrying an externally mounted 2A44 203 mm gun on the hull rear. The vehicle is self-entrenching and has an overpressure CBRN defense system. It was reported that the 12 m (39 ft) gun weighs 14.6 t (14.4 long tons; 16.1 short tons) and has a service life of 450 rounds.