Spike's Tactical Barrel, 223 Rem/556NATO, 14.5", Black Finish, Cold Hammer Forged, M4 Extension, 1:7 Twist SB51406-ML
Rosco Manufacturing Bloodline Barrel, 556NATO, 14.5", Black Nitride Finish, 1:7 Twist, 1/2x28, 4150 CMV BL-145-M4-556-7-C
Noveske Barrel, 556NATO, 14.5", 1:7 Twist, Mid Lenght GasSystem, Pinned Gas Block and Gas Tube, Stainless 07000054
Knights Armament Company SR-15, Carbine Mod2, Complete Upper Receiver, 556NATO, 14.5" Hammer Forged Barrel, Black Finish, MLOK 31949
FN America Barrel, 14.5", Hammer Forged, For AR Rifles, Carbine Length Gas System, Black System 36420
Daniel Defense Barrel, Light Weight, 556NATO, 14.5", 1:7 Twist, Mid Length Gas System, Black 07-078-08072-018
Daniel Defense Barrel, Government Profile, 556NATO, 14.5", 1:7 Twist, Mid Length Gas System, Black Finish 07-077-19125-018
Colt's Manufacturing Upper, 556NATO, 14.5", Black LE6921EPR-CK
Colt's Manufacturing Complete Upper Reciever, Fits AR, 223 Rem/556NATO, 14.5" Chrome Lined Barrel, 1:7 RH Twist, Magpul Flip-Up Rear Sight, M4 Contour Barrel, Standard Sling Swivel, Bolt Carrier Assembly and Charging Handle, Black Finish, Not Pinned and Welded LE6921CK