The Aero Precision M4E1 Stripped Upper is a bare upper receiver designed for AR-15 builders who want maximum customization options. Unlike a complete upper, it does not include components like the barrel, handguard, gas system, or forward assist and dust cover, allowing users to select and install these parts themselves. The M4E1 Stripped Upper is known for its enhanced design that integrates features typically found in billet receivers, such as a sleek profile and advanced functionality, while maintaining compatibility with Mil-Spec parts. This stripped upper is machined from high-quality 7075-T6 aluminum for strength and durability and comes with a pre-installed barrel nut that simplifies handguard installation. It features a flared ejection port for reliable brass ejection and is compatible with both Aero Precision handguards and standard AR-15 components. Finished with Type III hard anodizing, the M4E1 Stripped Upper provides excellent resistance to wear and corrosion, making it an ideal starting point for custom AR-15 builds focused on performance and style.