This is an Arsenal SLR-107FR semi-automatic rifle in 7.62x39mm, assembled by Arsenal Inc. in Las Vegas, Nevada on a Bulgarian-made stamped receiver. It has a left-side folding polymer buttstock, black polymer handguards and pistol grip, a removable muzzle brake and a side-mounted scope rail. Excellent condition. 

The receiver is marked "Model SLR 107FR," a 7.62x39 caliber line, "Made in Bulgaria" and "Arsenal Las Vegas"; the serial is stamped beside a circle-10 mark, and its last four digits are painted in white on the top cover. Arsenal's published specification for the SLR-107FR is a cold hammer-forged, chrome-lined barrel with 24x1.5mm right-hand muzzle threads. Arsenal's own product page lists the rifle as no longer available from the company.