The M4E1 Lower Receiver delivers billet aesthetics in a forged package. This custom-designed enhanced forging is machined from 7075-T6 Aluminum and compatible with all mil-spec AR15 parts. Aside from the visual upgrades, this custom-engineered design provides features that challenge much more expensive billet options and simplify the assembly process for the at-home builder.

M4E1 Lower Receiver Improvements:

Threaded Bolt Catch Roll Pin - Allows for simple installation of the bolt catch and virtually eliminates the chance to damage the finish during installation (pin included). 1/16" Hex Key required for assembly.
Integrated Trigger Guard - Eliminates the possibility of breaking the trigger guard tabs by integrating the trigger guard into the lower, creating a stronger more rigid platform to build upon.
Upper Tension Screw - Allows users to fine tune the fit of the upper and lower receiver using a nylon tipped tensioning set screw inserted in the grip tang of the lower receiver. This provides a tight fit with any standard AR15 upper receiver.
Threaded Takedown Pin Detent Recess - Allows user to easily install the Takedown Pin detent and spring with the use of a 4-40 set screw (no more launching detents across the room).
Increased Magwell Flare - Increased the flare of the magwell to aid in quick and efficient magazine changes.
Marked and milled to accept short-throw safety selectors, but will work with standard selectors as well.
Includes:

Stripped M4E1 Lower Receiver
Nylon tipped tensioning set screw
Threaded Bolt Catch Pin