Next Level Armament NLX556 AR15 556 Nato 16in Complete Upper Receiver Midlength 1-7 Twist Black. Built with the best parts on the market complete upper comes with all the upgrades standard. Why pay less for inferior parts and pay more to upgrade later? Specifications for Next Level Armament NLX556 AR15 556 Nato 16in Complete Upper Receiver: Manufacturer: Next Level Armament Caliber: 5.56x45mm NATO Barrel Length: 16 in Gas System Length: Mid Length Barrel Twist Rate: 1-7 Finish: Anodized Color: Black Gun Model: AR-15 Fabric/Material: 7075 T6 Aluminum Handguard Length: 16 in Gun Type: Rifle Gun Make: AR Platform Weight: 0.75 lb Magazine Included: No Package Contents: Next Level Armament NLX556 AR15 556 Nato 16in Complete Upper Receiver Roscoe Bloodline 16in Barrel NLX556 BCG w/ DLC NLX556 Ambidextrous Charge Handle NLA Billet Low Profile Gas Block NLA 13in Mlok Handguard NLX-5 Helix Flash Hider What firearm models does the manufacturer say Next Level Armament NLX556 AR15 556 Nato 16in Complete Upper Receiver is compatible with? The manufacturer suggests that Next Level Armament NLX556 AR15 556 Nato 16in Complete Upper Receiver is compatible with AR-15Next Level Armament NLX302: NLX556 AR15 556 Nato 16in Complete Upper Receiver Midlength 1-7 Twist Black