Aero Precision M4E1 Threaded Complete Upper, 8” .300 Blackout Barrel, R-ONE M-LOK Handguard

Overview

The Aero Precision M4E1 Threaded Complete Upper with R-ONE Handguard is engineered for shooters who demand a lightweight yet highly capable platform. Featuring an 8” .300 Blackout barrel paired with Aero’s slim R-ONE M-LOK handguard, this upper provides the strength, stability, and attachment space needed for tactical and personal defense builds. Precision-machined and fully assembled, it’s ready to complete your AR pistol or SBR setup.

Key Features

• M4E1 Threaded Assembled Upper Receiver with billet-look forging
• 8” .300 Blackout barrel with pistol-length gas system
• R-ONE M-LOK Handguard
• Full-length Picatinny top rail for optics and accessories
• Integrated QD sling sockets at 3, 6, and 9 o’clock positions
• Low-profile gas block and pistol-length gas tube included
• Port door and forward assist installed
• Complete and ready to install (no BCG or charging handle included)

Specifications

• Manufacturer: Aero Precision
• Model: M4E1 Complete Upper
• Caliber: .300 Blackout
• Barrel Length: 8”
• Gas System: Pistol-length
• Handguard: R-ONE M-LOK 
• Receiver: M4E1 Threaded Forged Upper
• Features: M4 feed ramps, billet-look forging, laser-engraved T-marks
• Handguard ID/OD: 1.3” / 1.5”
• Rail: Full-length Picatinny top rail
• Sling Mounts: Integrated QD sockets at 3, 6, and 9 o’clock positions
• Compatibility: Mil-Spec AR-15 upper receivers and barrels
• Assembly: Fully assembled (excludes BCG and charging handle)

Applications

Designed for AR pistol or SBR builds, the Aero Precision M4E1 Complete Upper with R-ONE M-LOK Handguard combines strength, lightweight design, and attachment versatility—perfect for tactical, hunting, or personal defense use.