• Is a 'Call to order' product.

1. The Aero Precision M4E1 Threaded Assembled Upper Receiver combines the durability of a billet receiver with the compatibility and affordability of a mil-spec upper.
2. It comes pre-installed with a forward assist and ejection port cover, and is compatible with standard AR-15 barrel nuts and handguards.
3. The upper receiver is forged from 7075 T6 aluminum, features a hardcoat anodized finish, and is designed to fit on standard AR-15 lowers.

Aero Precision’s M4E1 Threaded Assembled Upper Receiver gives you the best of two worlds: that badass looks and robustness of a billet receiver plus the easy parts compatibility (and price!) of a traditional mil-spec upper. And it comes with two nit-picky jobs done for you: the forward assist and ejection port cover are already installed. But there’s more... The M4E1 Threaded Assembled Upper Receiver is Aero Precision’s M4E1 Enhanced Upper with standard barrel threads up front so it can accept a standard AR-15 barrel nut and handguard attachment. The original M4E1 upper is configured for the proprietary attachment system Aero’s Gen 2 Enhanced or Atlas ’guards. This version gives you all the M4E1 upper features and lets you build your rifle with a different handguard. It’s ready to serve as the foundation of an exciting custom AR-15. Hardcoat anodized finish, matte black Laser-engraved T marks on the Picatinny top rail M4-type feed ramps .250" takedown pin holes Also available "stripped" - without forward assist & ejection port cover (#100-026-237) The Aero Precision M4E1 Threaded Assembled Upper Receiver is forged from 7075 T6 aluminum, like a regular mil-spec receiver, but with angular external contours that add the strength - and custom look - of a "billet" receiver. It accepts any mil-spec AR-15 bolt/carrier group (not included) and fits on a standard AR-15 lower - though it looks darned good paired up with Aero’s equally rugged, all-business M4E1 forged lower receiver.