The AR-STONER AR-15 A3 Upper Receiver Assembly chambered in 300 AAC Blackout is ready to be assembled to a complete lower and fired. This AR-STONER upper features a carbine length gas system for use with supersonic or subsonic ammo, a mil-spec bolt carrier group, a 16” heavy-profile barrel with a parkerized finish and lightweight, 15” free float, M-Lok handguard.

Securely mount popular accessories directly to the precision M-Lok cutouts and attach your sling to the integrated QD mounts with this optimum handguard. This sleek and ergonomic free float handguard meets shooters needs without sacrificing strength and performance.