This rifle is a variation of the widely known Russian SKS, invented by Sergei Gavrilovich Simonov in 1945. The Russian SKS was one of the first weapons chambered for the 7.62x39mm intermediate round later used in the AK-47 and RPK. During the Cold War, the Soviet Union's satellite states produced copies of the Soviet design for their own use. The M59/66 model was produced by Yugoslavian manufacturer Zastava from 1967 to 1970. The M59/66 differed from the M59 in that it has an integrated grenade launcher (standard 22mm NATO rifle grenade) and has an 11.5" folding bayonet.
This rifle is considered along with the US M1 Carbine a precursor to the Assault Rifle.