Andro Corp Complete Upper Features The Andro Corp Industries Complete Upper pairs an 8 inch chrome moly vanadium barrel with a 1:7 twist rate a combination well suited to stabilizing the heavier subsonic bullets often used in .300 Blackout builds as well as lighter supersonic loads. The 1/2x28 threaded muzzle gives the builder the option to add a muzzle brake flash hider or suppressor mount without needing additional gunsmithing. Chrome moly vanadium construction provides the strength and heat resistance needed for a barrel running in a compact pistol-length configuration. This short barrel length keeps the completed upper compact and maneuverable for close-quarters or truck gun builds. An M-LOK handguard covers the barrel giving the shooter a direct-attach mounting surface for lights lasers bipods or slings without needing separate rail sections. That handguard keeps the overall profile slim while still offering the flexibility modern AR builders expect from their rail system. Because this is a complete upper it arrives ready to mate to a compatible AR-platform lower simplifying the build process for anyone assembling a .300 Blackout pistol or short-barreled rifle. For builders looking for a ready-to-run 8 inch .300 Blackout upper with a threaded barrel and M-LOK rail the Andro Corp Industries Complete Upper is available for sale at GrabAGun. Andro Corp Complete Upper Specifications Manufacturer: Andro Corp Caliber: .300 Blackout Barrel Material: Chrome Moly Vanadium Twist Rate: 1:7 Barrel Length: 8 Thread Pattern: 1/2x28 Handguard: M-LOK Available At: GrabAGun