Product DescriptionThe CMMG Barrel Sub-Assembly is a dependable foundation for building or refreshing an AR-15 upper. This 16.10-inch 5.56x45mm NATO barrel is made from 4140 chrome-moly steel and finished in black nitride for enhanced wear and corrosion resistance. Built with an M4 profile and carbine-length gas system, it comes with a properly installed M4 barrel extension to help ensure correct fitment during your upper build.Product Highlights 16.10-inch AR-15 barrel sub-assembly designed for 5.56x45mm NATO chambering Durable 4140 chrome-moly steel construction with black nitride (salt bath nitride) finish Carbine-length gas system and M4 profile for a proven, versatile configuration Properly installed M4 barrel extension for simplified upper receiver assembly Threaded muzzle (1/2x28) for compatibility with common 5.56 muzzle devices and suppressor mountsSpecs Brand: CMMG Manufacturer Part Number: 55DE10A UPC: 815835014067 Type: Barrel Sub-Assembly Caliber/Chamber: 5.56x45mm NATO Barrel Length: 16.10 in Barrel Material: 4140 chrome-moly (chromoly) steel Finish/Color: Black nitride (salt bath nitride) Gas System Length: Carbine Profile: M4 Muzzle Threads: 1/2x28 Compatibility: AR-15 Barrel Extension: M4 (installed) Item Weight (approx.): 1.9 lbDisclaimer: We strive to provide accurate and up-to-date product descriptions, specifications, and images; however, errors or omissions may occasionally occur. We are not responsible for any inaccuracies or discrepancies in the content provided. If you notice anything incorrect or unclear, please contact us so we can correct it. When in doubt, we recommend verifying details directly with the product's manufacturer.