Sig Sauer MCX Upper 11.5" Barrel AR Conversion Kit, 5.56 NATO, Tapered Lug, MLOK. Available in 5.56 NATO, this conversion kit has everything needed to put a MCX upper receiver on an AR-15 lower, and includes: a Sig Sauer MCX upper, X-fold stock adapter, MCX to M400 (AR-15) lower receiver adapter, 90 degree muzzle adapter for standard non Sig Sauer suppressors, AR Two-Stage Matchlite DUO trigger kit and 1913 low profile QD socket with hardware. The kit features a 11.5" barrel with a thread pitch of 1/2" x 28 TPI.

The SIG Matchlite Duo trigger unit provides a crisp and clean feel, and a new tapered bolt lug design extends bolt life while resulting in smoother cycling. The MCX Virtus upper receiver assembly features a standard free-floating M-LOK handguard with a top picatinny rail for sight and optic, as well as a short-stroke piston system and unique internal recoil system that eliminate the M4-style buffer tube resulting in a light-recoiling and compact platform able to be configured for any task.

Includes:

• MCX Upper Assembly
• X-Fold Stock Adapter
• MCX to M400 (AR-15) Lower Receiver Adapter
• 90 Degree Muzzle Adapter for Standard Non Sig Sauer Suppressors
• AR Two-Stage Matchlite DUO Trigger Kit
• 1913 Low Profile QD Socket with Hardware
• MCX Owner's Manual

• Barrel Length: 11-1/2"
• Barrel Thread Pitch: 1/2" x 28 TPI
• Brand: Sig Sauer
• Caliber: 5.56x45mm
• Finish / Color: Black
• Firearm Type: Pistol,Rifle
• Material: Steel,Aluminum