Nexgen NG15 .223 Wylde Semi-Auto Rifle with Pewter Nitride Finish 15" M-LOK aluminum handguard with full-length Picatinny top rail Low-profile .750 gas block for a clean, lightweight profile Nitride bolt carrier group for enhanced durability Mil-spec charging handle 6-position adjustable stock Standard pistol grip Hard coat anodized finish Barrel Type: HBAR 4150 Chromoly nitride double stress relieved button rifled Muzzle: 1/2x28 threaded Twist Rate: 1:8 Upper Receiver: Aluminum billet Lower Receiver: Aluminum billet Gas System: Carbine length Gas Block: .750 low profile 4150 steel black oxide Stock: 6-position adjustable black Grip: Standard Finish: Hard coat anodized Pewter Magazine: 1 x 30-round polymer