No Sale To California: Other FEATURES: MACHINED From 7075-T6 Aluminum With Hard Coat Anodize Finish, Compatible With All Mil-Spec Internal Parts, Compatible With PMAGS/Gi Mags Other FEATURES2: Full Compatibility With All Other AFTERMARKET Mil-Spec Upper RECEIVERS, Multi-Caliber Marked Caliber: .223 (5.56mm Nato) Type Action: Semi-Automatic Rate Of Twist: Receiver Only Metal Finish: Black Stock Material: Lower Receiver Only Barrel Length In INCHES: 0 Overall Length In INCHES: 0 Magazine Capacity: 0 Detachable Magazine: Y Hinged Floorplate: N Sights: N