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Perfect for an SBR or AR Pistol

The Critical Capabilities barreled Upper Receiver in 9mm offers the optimal combination for those wanting to assemble an SBR, or AR pistol.

The genesis of your next build features a 7075-T6 Flat Top M4 Upper Receiver and a 4” Aluminum Rail with M-LOK attachments.

  • Forged 7075-T6 Flat Top M4 Upper Receiver
  • 5.5” Chrome Moly Nitride Treated Barrel
  • 1-10 RH Twist
  • 4” Free Float 6061-T6 Aluminum Rail w/ M-LOK

The Critical Capabilities Upper Receiver does not include a BCG or charging handle, meaning you can choose ideal components based upon its intended use.

CRITICAL CAPABILITIES LLC - AR-15 5.5" 9MM UPPER RECEIVER W/4" M-LOK RAIL NO BCG OR CH

No longer deliverable by the Factory

Cartridge: 9 mm Luger

Finish: Black

Style: M-LOK

Length: 5.5"

Twist: 1-10