These products may be selected as add-ons under the FINISH YOUR BUILD tab; The muzzle brake that comes with this complete upper receiver is NOT pinned nor welded to this barrel. These products may be selected as add-ons under the Finish Your Build tab; The muzzle brake that comes with this complete upper receiver is NOT pinned nor welded to this barrel. The muzzle brake that comes with this complete upper receiver is NOT pinned nor welded to this barrel. $94.99 (10) $124.99. This complete upper does not include BCG or Charging Handle. Aero Precision M4E1 Threaded Assembled Upper Receiver: Aero Precision M4E1 Threaded Assembled Upper Receiver - FDE: $99.99. AERO Precision M4E1 Threaded 20" .223 Wylde Fluted Complete Upper at the Best Price Online, on Sale w/ FREE Shipping from Xtreme Guns and Ammo Per the National Firearms Act, the muzzle brake MUST be pinned and welded to achieve the necessary 16" as defined by the ATF for a rifle build. This complete upper does not include BCG or Charging Handle. Complete Uppers M4E1 Threaded Complete Upper, 16" 5.56 M4 Barrel, ATLAS R-ONE 15" M-LOK HG DUE TO HIGH ORDER VOLUME PLEASE ALLOW 2-3 ADDITIONAL BUSINESS DAYS TO PROCESS AND SHIP YOUR ORDER. 3 Customer Reviews Write A Review. M4E1 Threaded Upper Receiver Features: M4 Feedramps.250 takedown pin holes; Laser engraved T-marks This complete upper does not include BCG or Charging Handle. The M4E1 Threaded Upper Receiver features a new angular machined design that helps it stand apart from standard mil-spec upper receivers. This complete upper does not include BCG or Charging Handle. IN ADDITION, MOST SHIPPING CARRIERS ARE EXPERIENCING SLIGHT DELAYS. The muzzle brake that comes with this complete upper receiver is NOT pinned nor welded to this barrel. Rating: 100 % of 100. M4E1 Threaded 7.5" 5.56 Complete Upper Receiver w/ 7" M-LOK ATLAS R-ONE Handguard. Out of stock. Add to Wish List Compare Product. $139.99. M4E1 Threaded Upper Receiver Features: New enhanced forging that gives the upper receiver a "billet look" The S-ONE line of handguards are designed with size and weight in mind, providing the perfect addition to your lightweight build. These products may be selected as add-ons under the Finish Your Build tab; The muzzle brake that comes with this complete upper receiver is NOT pinned nor welded to this barrel. M4E1 Threaded Upper Receiver Features: New enhanced forging that gives the upper receiver a "billet look" M4E1 Threaded ATLAS S-ONE 5.56 Complete Uppers include the new ATLAS S-ONE Handguard! M4E1 Threaded 10.5" 5.56 Complete Upper Receiver w/ ATLAS … Aero Precision complete mil-spec AR-15 upper receiver. Aero M4E1 Threaded Complete Upper, 16" 5.56 Mid-Length Barrel, 15" M-LOK ATLAS S-ONE Handguard DUE TO HIGH ORDER VOLUME PLEASE ALLOW 2-3 ADDITIONAL BUSINESS DAYS TO PROCESS AND SHIP YOUR ORDER.