Spikes Tactical Upper 5.56 16in Midlength LE w/9in BAR2 Rail and FSP Black. 56 LE Midlength 16in Forged Upper Receiver that's inspected and ready to function right out of the box. Spikes Tactical crafted these AR15 Upper Receivers from 7075 T6 aluminum to add an element of toughness to your build without the added weight of heavy steel. The Spikes Tactical 5.56 LE Midlength 16in Drop-In Upper comes with everything you need to complete your upper build including a phosphate-coated bolt carrier group that resists corrosion to provide countless years of service. Bring some serious function and power to your build by installing this Spikes Tactical 5.56 LE Midlength 16in Complete Upper Assembly. Specifications for Spikes Tactical 5.56 LE Midlength 16in Forged Upper Receiver: Manufacturer: Spikes Tactical Caliber: 5.56x45mm NATO Barrel Length: 16 in Color: Black Gun Model: AR-15 Gun Make: AR Platform Magazine Included: No Country of Origin: USA Features of Spikes Tactical 5.56 LE Midlength 16in Forged Upper Receiver: Forged Upper Receiver: 7075 T6 Construction Forward Assist Ejection Port Door Ejection Port Door Spring Ejection Port Door Rod 16in Mid Length Barrel: MIL-B-11595E CMV Chrome Lined 1/7 Twist Rate 1/2 X 28 Thread Pitch for Muzzle 5.56 Nato Chamber .750 Gas Block Seat M4 Feed Ramped Barrel Extension Mil-Spec Phosphate Coating Delta Ring Assembly: Mil-Spec Barrel Nut Delta Ring Weld Spring Snap Ring A2 Front Sight Base Pinned: Front Sight Post FSP Detent FSP Detent Spring Magpul SL Handguard: Black Mid Length Gas Tube: Black Nitride Inside and Out Gas Tube Roll Pin Charging Handle: Forged Aluminum Mil-Spec Type 3 Coating Phosphate M16 Complete BCG: Phosphate Coated Laser Engraved with ST Spider logo High Pressure Tested (HPT) Magnetic Particle Inspected (MPI) A2 Flash Hider: 0.5in Crush Washer Package Contents: Spikes Tactical 5.56 LE Midlength 16in Forged Upper Receiver What firearm models does the manufacturer say Spikes Tactical 5.56 LE Midlength 16in Forged Upper Receiver is compatible with? The manufacturer suggests that Spikes Tactical 5.56 LE Midlength 16in Forged Upper Receiver is compatible with AR-15Spikes STU5035-CQ9FP ST-15 LE Mid Upper 5.56 16 9 SAR Quad Rail Black