Bolt Finish: Manganese Phosphate coating (Parkerized)
Bolt Material: 9310 Steel
Caliber Gauge:5.56 NATO
Carrier Finish:Salt Bath Nitride
Carrier Material:9310 Steel Carrier
Magnetic Particle Inspect:Magnetic Particle Inspected
Platform: AR-15
 
Includes Bolt, Bolt Carrier, Extractor Pin, Firing Pin, Cam Pin

Direct Link: https://3crtactical.com/product/nitride-bolt-carrier-group-5-56-223/