AERO PRECISION M4E1 Complete Upper 5.56 NATO 16" HBAR CMV Barrel, 15" ATLAS R-ONE M-LOK Handguard

Faxon Firearms M4 Button Rifled Barrel 5.56x45mm 16", Black

Faxon Firearms Mid-Length Button Rifled Gunner Barrel 5.56x45mm 16", Black

Ballistic Advantage Performance Barrel 5.56x45mm 13.70", Black - Compact and Efficient Barrel - BABL556036F

Radian Weapons Model 1 MOE Upper M-LOK Rail with Charging Handle, Black - Elite Tactical - R0192

CMMG Resolute 16.10" Upper 8.6 Blackout 1:3 M-LOK Rail Carbine-Length, Armor Black

AERO PRECISION M4E1-T 5.56 NATO 11.5" Complete Upper Receiver | Black

SPIKES TACTICAL Barrel 223/5.56 16" Hammer Forged fits AR Rifles