Bolt Carrier Group Specs:
* M16 "Full Auto Capible Carrier" Works with all AR15 rifles!
* Carrier made of hardened 8620, chrome-lined interior, magnesium phosphate coated exterior
* Gas Key 4140, chrome-lined interior, magnesium phosphate coated exterior
* Bolt made of hardened 9310 - 5.56/.223/300blk caliber bolt face
* Gas Key Hardened to USGI Specifications
* Gas Key Grade 8 Hardened Fasteners
* Gas Key Staked Per Mil-Spec
* Tool Steel Extractor
* Extractor Spring

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