Optimize your AR-15 with the Recoil Technologies Premium Bolt Carrier Group, engineered for reliability and performance in various calibers. This complete bolt carrier group is precisely crafted in the USA, ensuring quality that you can trust for your shooting needs. Its robust materials and finishes enhance durability while maintaining peak functionality. Caliber Compatible: 5.56/.223/.300/.350 Material: 9310 Alloy Steel Bolt Head, 8620 Alloy Steel Body Finish: Nitride for improved corrosion resistance Style: Standard, Full Auto Compatible Gas System: Direct Impingement Forward Assist Machining: Yes Upgrade your firearm's performance with the reliability of Recoil Technologies.