Action: Semi-Automatic Ambidextrous Safety: No Barrel: 18 inch, 1:24 Twist – Either 416R SS or 4150 CRMOV Nitride, 11/16 x 24 threads Caliber: .450 Bushmaster Feed Ramps: Modified M4 Finish: Cerakote Frame Material: Aluminum 7075 Gas System: 0.750 Gas Block and Mid Length Gas Tube Grip: Mil-spec, Polymer Handguard: 15.25" Aluminum 6061 – Full picatinny rail Magazine Capacity: 5 Round Mags included: 1 Muzzle Brake: Included - Designed to be 6 degrees forward, wrench tightened w/o Loctite Sights: None Trigger: Milspec, 5.5-6 lb pull Upper Receiver: 7075 Oversized Upper Overall Length: 35.00” Weight: 6.4 lbs