AR-15 Upper Receiver Cqb Mod 2 11.5" URX 4 M-LOK

Prices last checked September 2026. Prices and availability change often, so confirm on the retailer's site.

Knight’s Armament Company, or KAC, is known to many for their top tier, military issued rifles and parts.

Brownells is proud to offer this line of Knight’s Armament SR-15 MOD 2 complete upper receivers that allow you to easily complete a build or upgrade a rifle with battle proven quality.
Built around a chrome lined, cold hammer forged barrel in your choice of 11.5”, 14.5” 16” & 18” lengths with a Mod 2 gas block, and fitted with a KAC 3 prong QDC suppressor compatible flash hider.

The Knight’s Armament SR-15 MOD 2 complete upper receivers feature the URX M-LOK handguards that each have 2 anti-rotation QD sling swivel sockets and even includes a Magpul M-LOK rail cover kit.

On top you’ll find the KAC Micro Front Sight and at the rear the KAC 200-600m micro rear sight that is flip up and adjustable for windage and elevation.

The included bolt carrier group features the E3 bolt that has rounded locking lugs that work in conjunction with the E3 barrel extension.

Also included is an extended latch charging handle.
The 14.5” MOD 2 complete upper receivers’ flash hider does not come from the factory pinned to the barrel.

Knight’s Armament HH buffer comes with the 11.5" and 14.5" upper receivers only, as the shortened gas systems require it for proper function.