Sig Sauer SIG516 14.5" Upper Receiver Assembly - 5.56x45 NATO Short-Stroke Piston
This Sig Sauer SIG516 upper receiver assembly features a short-stroke gas piston operating system with a 4-position adjustable gas valve (normal, adverse, suppressed, and off). It is built around a 14.5" M4-profile barrel chambered in 5.56x45 NATO with a nitride-treated finish.
The upper is fitted with a free-floating aluminum handguard and a full-length Picatinny top rail, with a flash hider/muzzle device installed on a 1/2x28 threaded muzzle. Bolt carrier group and charging handle are installed.