This is an excellent post war submachine gun as manufactured at Zastava the Yugoslavian Arsenal. It was developed in 1948 and fully adopted in by the Communist Yugoslavian Army in 1949. The top of the receiver is stamped with the Yugoslavian/communist crest over "m49/57". It has an all blued metal finish and a European walnut/hardwood type buttstock. This example is actually an updated version fielded in 1957 that has the slightly longer barrel and a large push button bolt lock on the underside of the receiver just in front of the trigger guard bow. This bolt lock can also act as a safety and can lock the lock in either the closed or open position. This model is actually based on the WWII Russian PPSH41 in that is basically made from two different sections, a stamped and welded magazine well/center section, and a tubular perforated barrel jacket with a rear receiver section. The tubular barrel jacket/rear receiver section is inserted through the magazine well and pinned in place to form the complete receiver. The lower trigger housing is also a stamped and welded section that is attached to the receiver. It fires from an open bolt with a fixed firing pin and has a sliding selector switch (for semi and full automatic fire) in front of the trigger. It fires the standard Russian 7.62x25mm pistol cartridge same as the Russian PPSH41 and PPS43 SMGs. A very simple to manufacture but robust SMG. This example is fitted with a black rubber recoil boot on the end of the stock. Magazine absent; however they probably use the same Russian PPSH41 type magazines.