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Knights Armament - SR-15 E3 Mod2 CQB 11.5" - Complete Upper


The SR-15E3 CQB Mod 2’s 11.5” chrome lined, 5.56mm NATO barrel is manufactured for military grade durability, and is free-floated inside a 10.75” URX4 handguard. An improved E3 round-lug bolt design both enhances function and increases bolt life far beyond the industry standard.

Comes with front and rear BUIS, bolt and carrier, charging handle, buffer, three prong QDC flash hider, picatinny rail section, and rail panel kit.


Barrel: 11.5 inch chrome lined, 1:7 twist, chrome lined, hammer forged

Rail: URX4 - The URX4 keymod rail system features a stronger and more stable designs over previous rail systems due to its one piece construction.

Gas system: Carbine length

Bolt Carrier Group: The bolt carrier group features the revolutionary E3 bolt design. The E3 design increases the durability and life of the bolt by utilizing features such as rounded lugs, size reduction of the cam pin, larger bolt face, and a proprietary extractor design.

Sights: Micro rear 600m flip up sight and Micro front flip up sight.

Muzzle Device: Quick Detach Coupler (QDC) Suppressor ready three prong flash hider (Length 2.17")

Charging handle: Knights Armament enhanced charging handle

KAC Proprietary buffer is included with the 11.5 upper. Combining the proprietary gas system and buffer weight produces a noticeable increase in how smooth the rifle operates when compared to standard a AR-15.

All NFA rules and regulation apply*

Does not need to ship to FFL