This complete upper is equipped with the highly regarded Atlas R-One handguard, meticulously designed to deliver the perfect balance of size and weight. Despite its slim profile, the R-One handguard offers ample real estate to accommodate a wide range of accessories, ensuring you can tailor your firearm to meet any mission requirements. Featuring the proprietary Atlas attachment system, it provides a rock-solid mounting platform that combines durability with ease of use. Aero Precision's signature commitment to strength and stability is evident in the R-One, making it a reliable choice for both tactical and recreational use. Whether you're outfitting your rifle for performance or customization, the Atlas R-One handguard enhances both function and aesthetics.

The M4E1 threaded assembled upper receiver offers a durable and reliable platform for easy assembly, ensuring a tight fit for your components
The 9 inches M-LOK Atlas S-ONE handguard offers a strong, lightweight design for superior performance
Features a 10-1/2 inches 5.56 CMV barrel
The low-profile gas block paired with a carbine-length gas tube provides smooth, reliable cycling while maintaining a compact and efficient design
Product comes assembled, ready for immediate use without the need for additional assembly or setup
The complete upper does not include a BCG or charging handle, allowing you to customize your build

Report incorrect product description

Reviews

Q & A

Retail Stock

Compliance

Shipping Restrictions

It is the customer’s responsibility for understanding state laws regarding all purchases made. For a comprehensive list of all Shipping Restrictions, please refer to our Shipping Restrictions By State Page found Here.

All NFA Rules Apply

These items are controlled by the U.S. Government and authorized for export only to the country of ultimate destination for use by the ultimate consignee or end-user(s) herein identified. They may not be resold, transferred, or otherwise disposed of, to any other country or to any person other than the authorized ultimate consignee or end-user(s), either in their original form or after being incorporated into other items, without first obtaining approval from the U.S. government or as otherwise authorized by U.S. law and regulations.

Local Law Compliance

Certain firearm parts and accessories, including AR-style upper receivers, are subject to complex and frequently changing federal, state, and local laws and regulations. While an upper receiver may be lawfully sold and shipped as a component, the legality of possessing, assembling, configuring, or using an upper receiver in certain states (e.g., California, Washington State) and localities depends on how it is assembled, combined with other components, and ultimately used. You are solely responsible for ensuring that any assembly, configuration, possession, or use complies with all federal, state, and local laws, including any so-called “assault weapon” bans and short-barreled rifle restrictions. We do not provide legal advice and are not responsible for unlawful configurations or uses.