Colt AR-15 Pistol Upper Receiver Assembly 5.56x45mm Monolithic Rail

Build a battle-proven tactical setup with the Colt AR-15 Pistol Upper Receiver Assembly 5.56x45mm Monolithic Rail. Engineered to true military-grade standards, this premium AR pistol upper features Colt’s iconic monolithic upper receiver design—machined from a single solid forging of aircraft-grade aluminum for unrivaled structural strength, reduced handguard flex, and zero movement when mounting laser sight systems or optics.

Chambered in 5.56x45mm NATO, this complete pistol upper receiver is equipped with a high-grade Chrome-Lined barrel, heavy-duty bolt carrier group, and full-length continuous top Picatinny rail with modular rail section attachments. Built for hard-use applications, home defense setups, and Short-Barreled Rifle (SBR) configurations, Colt’s monolithic pistol assembly delivers true duty-tier reliability and pinpoint return-to-zero accuracy.

• Caliber: 5.56x45mm NATO (.223 Remington compatible)

• Receiver Style: One-Piece Monolithic Aircraft Aluminum Forging

• Barrel Finish: Chrome-Lined for maximum corrosion resistance and barrel life

• Top Rail: Continuous Full-Length Picatinny Quad/Modular System

• Included Components: Complete Bolt Carrier Group (BCG) and Charging Handle

• Use Case: Custom AR pistol builds, Short-Barreled Rifle (SBR) setups, home defense, and tactical law enforcement applications

Features

Monolithic Rail
Free-Floating Barrel
Flat Top Upper
A2 Flash Hider
Black Parkerized Finish
Flip-Up Rear Sight

Note the design of the rear sight may vary as Colt production specifications change. Current uppers are being received with either Magpul or MaTech style adjustable flip-up rear sights.

Colt logo
Made In United States of America
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