Most popular upgrade lower receiver. Forged 7075-T6 with integrated trigger guard, threaded bolt catch pin, and upper tension screw.

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Aero Precision's M4E1 Stripped 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 AR-15 parts. The M4E1 provides features that challenge much more expensive billet options while simplifying the assembly process for at-home builders.
The standout feature is the threaded bolt catch roll pin, which allows simple installation using a standard hex key rather than hammering in a roll pin. This virtually eliminates the chance of damaging the finish during installation and makes the bolt catch installation accessible to first-time builders. The integrated trigger guard creates a stronger, more rigid platform by eliminating the separate trigger guard tab that can break on standard lowers.
The upper tension screw allows users to fine-tune the fit between upper and lower receivers, eliminating wobble for a tighter, more accurate platform. Combined with the flared magwell for faster reloads and clean styling that rivals expensive billet receivers, the M4E1 represents exceptional value for PDW and general AR builds alike.

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Add the Aero Precision M4E1 Stripped Lower Receiver to your build and see how it enhances your platform.