This MICRO AR15 upper receiver assembly comes ready to attach to any Mil-Spec lower receiver. The receiver is a flat top M4 forged Mil-Spec upper receiver that is CNC Machined from 7075-T6 aluminum -  the hardest and most durable material of any upper. The MICRO 5” 5.56 NATO barrel is manufactured with 4150 Chrome Moly steel and has a 1:5 twist rate & MICRO gas system. This upper assembly features an Afterburner linear compensator for improved handling and accuracy. Barrel: 5″ 5.56

***No BCG or CH included at this price***