Fostech AR-15 Complete Lite Bolt Carrier Group BCG Low Mass Nickel Boron Coating FT-BCG-NB-LOWMASS. These Bolt Carrier Groups by FosTech Outdoors are constructed out of nickel boron ensuring the best quality and performance possible for your rifle. This FosTech Outdoors AR-15 Lite Low Mass Bolt Carrier Group has a Nickel Boron finish to reduce friction and resist wear ensuring this Bolt Carrier Group lasts through many years of use. When you need a reliable and lightweight bolt carrier group for your AR-15 choose the FosTech Outdoors AR-15 Lite Bolt Carrier Group w/ Low Mass. Specifications for Fostech AR-15 Complete Lite Bolt Carrier Group (BCG) Low Mass: Manufacturer: Fostech Finish: Nickel Boron Carrier Material: 8620 Steel Bolt Material: 9310 Steel Gun Make: AR Platform Gun Model: AR-15 Condition: New Features of FosTEch AR-15 Complete Lite Bolt Carrier Group BCG: Nickel Boron Plating Fits Mil-Spec AR 15 Upper Receivers Made From Stainless Steel Package Contents: Fostech AR-15 Complete Lite Bolt Carrier Group Low Mass What firearm models does the manufacturer say Fostech AR-15 Complete Lite Bolt Carrier Group (BCG) Low Mass is compatible with? The manufacturer suggests that Fostech AR-15 Complete Lite Bolt Carrier Group (BCG) Low Mass is compatible with AR-15Fostech FT-BCG-NB-LOWMASS: AR-15 Complete Lite Bolt Carrier Group Low Mass Nickel Boron Coating