The K1 tank is a third-generation main battle tank operated by the Republic of Korea Army. It is also known by the nicknames 88 Tank and K1 88 Tank. However, in military circles, it was referred to as the XK1 tank during the ROKIT development project. Even when it was officially deployed in 1987, its official name remained the K1 tank. An upgraded version, the K1A1 tank, has since been developed.