Product DescriptionThe Battle Arms Development WORKHORSE complete upper receiver is built around a forged WORKHORSE 7075-T6 aircraft-grade aluminum receiver and a free-float WORKHORSE M-LOK handguard for a strong, reliable AR-15/M4 upper. A full-length Picatinny top rail with the signature notch cut provides consistent accessory alignment. The 16-inch 4150 chrome-moly steel barrel features a black nitride finish for durability and accuracy, and is individually headspaced with the included bolt carrier group for dependable performance and easier cleaning. This complete upper includes an ambidextrous Rack-15-C charging handle and arrives in a durable black anodized finish.Product Highlights 16-inch 4150 chrome-moly steel barrel with black nitride finish for long-lasting wear resistance Forged WORKHORSE 7075-T6 aluminum upper receiver for strength with AR-15/M4 compatibility Free-float 15-inch M-LOK handguard with attachment points at 3, 6, and 9 o'clock plus full-length Picatinny top rail Includes AR-15/M16 bolt carrier group and Rack-15-C ambidextrous charging handle Carbine-length gas system and A2 flash hider with 1/2-28 muzzle threadsSpecs Brand: Battle Arms Development Manufacturer Part Number: WH-UR16B-Y-15C UPC: 810033786167 Platform: AR-15/M4 Barrel Length: 16 in Chamber: .223 Wylde Gas System: Carbine Barrel Profile: A2 Barrel Steel: 4150 Chrome-Moly Vanadium Barrel Finish: Nitride Twist Rate: 1:8 Receiver Material: Forged 7075-T6 aluminum Receiver Type: M4 Handguard: WORKHORSE 15 in M-LOK free-float rail Muzzle Thread: 1/2-28 Muzzle Device: A2 flash hider Gas Block Diameter: 0.750 in Bolt Carrier Group Included: Yes Charging Handle Included: Yes, ambidextrous (Rack-15-C) Overall Length: 24.875 in Color/Finish: Black anodizedDisclaimer: 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.