The Sons of Liberty Gun Works M4-L89 URG 14.5" 5.56 No MD Upper Receiver Group is built for shooters who want a dependable, hard-use AR-15 upper without unnecessary extras. Featuring a 14.5" 5.56 NATO Liberty Fighting Barrel and a 13.75" L89 handguard, this assembly offers a balanced profile with generous M-LOK real estate for lights, grips, and other accessories. The forged upper receiver and Drivelock barrel nut system are designed to deliver solid lockup and long-term durability.

This upper is ideal for range training, practical competition, and general-purpose defensive setups when paired with a compatible lower. The extended 7-sided M-LOK rail provides flexible mounting options while keeping weight manageable, and the integral QD sockets at the barrel nut make sling setup straightforward. With Sons of Liberty Gun Works’ reputation for reliable, well-built components, the M4-L89 URG is a strong foundation for a quality AR-15 build.

Key Features:

• Manufacturer: Sons of Liberty Gun Works
• Model: M4-L89 Upper Receiver Group
• Caliber: 5.56x45mm NATO
• Barrel Length: 14.5"
• Rail Length: 13.75" L89 Handguard
• Condition: New
• Action: Semi-Automatic (upper receiver group for AR-15)
• Unique Features: 7-Sided M-LOK Slots, Integral QD Sockets At Barrel Nut, Drivelock Barrel Nut System
• Weight: 3.81 lbs
• Length: 30.25"
• Width: 3.25"
• Height: 3.00"