Pro2A Tactical 6.8 SPC II / 224 Valkyrie Nitride Bolt Carrier Group

224 Valkyrie/ 6.8 SPC II Nitride M16 Bolt Carrier Group by Pro2A Tactical. Made for us by one of the largest BCG manufacturers in the country. Carrier Specifications Material: 8620 Steel Type: M16 Full Auto (Preferred for most AR-15 builds) Gas Key Material: 4130 Steel; Grade 8 Gas Key Screws Coating: Black Nitride Bolt Specifications Bolt Material: 9310 Steel | Shot Peened Extractor Material: 4140 Steel Caliber: 6.8 SPC II / 224 ValkyrieMil-Spec O-Ring Mil-Spec Gas Rings (3) Cam Pin Material: 8620 Steel Firing Pin Material: 416 Stainless Steel Other: MPI Inspected Lifetime Warranty - Our BCGs carry a limited lifetime warranty to the original buyer. Simply put... Should any our BCGs fail, return it to them for a brand new replacement.