M4E1-T 14.5 Upper 5.56 Carbine W/ 12 M-LOK Atlas R-One

A Complete Aero Precision Upper Receiver With Your Handguard of Choice

Once you've finished your AR-15 lower receiver build, it's time to match that lower with an upper receiver. The work involved in building an upper receiver isn't much, so the cost savings between a fully built upper and upper-receiver components is negligible. So why not just have a fully assembled upper shipped right to you? These Aero Precision M4E1-T Upper Receivers are designed to drop right onto your lower with no added work needed.

Both upper receivers are equipped with 14.5-inch barrels that feature pinned-and-welded Epsilon SL muzzle brakes that bring the overall length to 16 inches, making them non-NFA firearms. The slim profile of the Epsilon muzzle brake allows users to swap out gas blocks without having to remove the brake.

Each Aero Precision M4E1-T Upper Receiver comes completely assembled in either mid-length or carbine-length gas systems. Consumers can also choose between the company's R-ONE or S-ONE handguards, and a port door and forward assist are included. A charging handle and bolt-carrier group are not included, however.