This lower receiver features Benjamin Franklin's political cartoon "Join, or Die" engraved on the magwell. This design was created in 1754 to represent the need for unification among the Thirteen Colonies later becoming an iconic symbol leading up to and during the American Revolution. The cartoon was used to encourage Colonists to stand together as it was pivotal to the success of the Revolutionary War. This design remains symbolic of American pride, perseverance, and unification nearly 250 years later.

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 that challenge much more expensive billet options, we have added several functional features to the lower receiver to simplify the assembly process for the at home builder. Blemished parts are not subject to Aero Precision warranty.