5.56x45mm NATO Barrels

16" 5.56 NATO 1:7 Twist Phosphate Midlength Lightweight Barrel

16" 5.56 NATO 1:9 Twist Phosphate Carbine Lightweight Barrel

16" 5.56 NATO 1:9 Twist Black Nitride Carbine Lightweight Barrel

16" 5.56 NATO 1:9 Twist Phosphate + Chrome-Lined Carbine M4 Barrel

16" 5.56 NATO 1:8 Twist Phosphate Carbine Government Barrel

20" 5.56 NATO 1:9 Twist Phosphate Rifle Lightweight Barrel

20" 5.56 NATO 1:9 Twist Phosphate Rifle Government Barrel

20" 5.56 NATO 1:9 Twist Phosphate Rifle Heavy Barrel

16" 5.56 NATO 1:9 Twist Phosphate Carbine Heavy Barrel

20" 5.56 NATO 1:9 Twist Phosphate + Chrome-Lined Rifle Heavy Barrel

16" 5.56 NATO 1:9 Twist Phosphate Carbine M4 Barrel

Daniel Defense 5.56 NATO 11.5" 1:7 Contract Overrun Upper Receiver w/DD4 7.0 Handguard

20" 5.56 NATO 4150 CMV Black Nitride CHF Govt 1:8 Rifle Length Barrel

20" 5.56 Government Contour 1:9 Rifle Length Barrel w/ FSB - Phosphate

14.5" 5.56 Chrome-Lined M4 1:9 Carbine Length Barrel w/ FSB - Phosphate

Aero Precision M4E1-T Threaded 18" 5.56 AR 15 Upper Assembly

16" 5.56 NATO 1:8 Carbine Length M4 Barrel - Black Nitride

16" 5.56 NATO 1:7 Mid-Length Lightweight Barrel - Black Nitride

13.9" 5.56 NATO 1:7 Black Nitride Midlength Pencil Barrel

14.5" 5.56 NATO 1:7 Black Nitride Midlength Pencil Barrel

20" Black Nitride 4150 Steel Heavy Barrel, 5.56 NATO, Rifle Length Gas System

16" 5.56 16" Parkerized Carbine Heavy Barrel

16" AR 15 Pencil Barrel 5.56 NATO

16" 5.56 HBAR Fluted Stainless Midlength M-LOK Upper Assembly