The SPG Kalina (Polish: Specjalne Podwozie Gąsiennicowe; SPG - lit. Special-purpose Tracked Chassis; Kalina is Polish for guelder rose) is a heavy, multi-purpose armoured personnel carrier designed at the OBRUM (OBRUM stands for Ośrodek Badawczo-Rozwojowy Urządzeń Mechanicznych – Polish for Research and Development Centre for Mechanical Appliances) and is produced by the Bumar Łabędy company - part of Polish military consortium - Bumar Group. SPG is a development of the joint Poland, Soviet Union and East Germany transporter called MT-S, developed in the late 1980s.