DPMS AR-15 Complete Upper Features The DPMS AR-15 Complete Upper is chambered in 5.56 NATO and built around a 16 inch barrel with a 1:7 inch twist rate a fast twist that stabilizes heavier bullet weights for duty and sporting use alike. The black phosphate finish on the barrel and internals provides corrosion resistance and reduces glare both of which matter for a build meant to see regular use. A fixed A2 front sight base keeps the front sight picture consistent while the included rear MBUS flip sight gives the shooter a usable rear reference without buying a separate optic first. Because this upper ships complete with its own bolt carrier group and charging handle it can be mated to any compatible mil-spec AR-15 lower without sourcing additional internal parts. That makes it a straightforward way to finish a build or swap calibers and configurations without reworking an existing lower receiver. The semi-automatic action and standard AR-15 pattern keep maintenance and parts compatibility simple for owners already familiar with the platform. Builders looking for a ready to install 5.56 upper will find this DPMS assembly a convenient option for sale at GrabAGun. DPMS AR-15 Complete Upper Specifications Manufacturer: DPMS Model: AR-15 Complete Upper Caliber: 5.56 Barrel Length: 16 Twist Rate: 1:7 Finish: Phosphate Action: Semi Automatic Color: Black Includes: Bolt Carrier Group Charging Handle Rear MBUS Sight A2 Front Sight Available At: GrabAGun