Aero Precision APAR600220M76: This Complete Upper includes Aero Precision\'s Gen 2 Enhanced Handguard! Key features include the addition of quick disconnect sling sockets, enhanced milling design for grip and visual appeal and a new profile for the picatinny top rail. This complete upper does not include BCG or Charging Handle. Includes: M4E1 Enhanced Upper Receiver 16.6\" Enhanced M-LOK Handguard 18\" .223 Wylde Stainless Steel QPQ Barrel, Rifle Length Low Profile Gas Block and Rifle Length Gas Tube A2 Flash Hider Product comes assembled M4E1 Upper Receiver Features: Forged from 7075 T6 aluminum Precision machined to M4E1 specs M4 feedramps Matte black hard coat Anodized Blackd Mil 8625 Type 3 Class 2 Laser engraved T-marks Comes assembled, with port door and forward assist installed Accepts standard AR15/M16 components Handguard mounting platform is forged into the receiver Works with Aero Precision handguards but also fits most BAR-system handguards Barrel nut and wrench are included Gen 2 Enhanced Handguard Features: 1pc free float design Built in anti-rotation tabs Scalloped rails Continuous top rail 1.78\" inside diameter fits most muzzle devices and 1.5\" suppressors Compatible with low profile gas blocks Gen 2 Feature - Quick disconnect sling socket at the 3, 6 and 9 o\'clock positions Gen 2 Feature - Additional milling along flats to aid with gripping and add visual appeal Gen 2 Feature - New profile for the continuous picatinny top rail 18\" .223 Wylde Stainless Steel QPQ Barrel, Mid-Length Features: .223 Wylde 18\" Mid Length Barrel, 1/8 Twist QPQ Corrosion Resistant Finish .750 gas block journal Rifle length gas system M4 Feed Ramp Extension HP and MPI tested Standard A2 flash hider