5.56x45mm NATO Upper Receivers

Dirty Bird 10.3" 5.56 NATO 1:8 V2 M-LOK Upper Assembly - Sniper Grey

Dirty Bird 10.3" 5.56 NATO 1:8 V2 M-LOK Upper Assembly - Midnight Bronze

Dirty Bird 10.3" 5.56 NATO 1:8 V2 M-LOK Upper Assembly - OD Green

Dirty Bird 10.3" 5.56 NATO 1:8 V2 M-LOK Upper Assembly - FDE

Dirty Bird 10.3" 5.56 NATO 1:8 V2 M-LOK Upper Assembly - Black

Dirty Bird 20" M16A1 Enhanced 5.56 Retro Upper Assembly - M4 Feed Ramps

NBS 11.5" Slick Side 5.56 Nitride-Carbine M-LOK Upper Assembly

NBS Premium Series 10.5 5.56 Upper Assembly w/ Geissele MK4 Handguard

NBS Premium Series 16 5.56 Upper Assembly w/ Rosco Barrel and Geissele MK14 Handguard

NBS Premium Series 16" Upper Assembly w/ BA Barrel and Geissele MK8 Handguard

BCM 5.56 NATO Midlength Barreled Upper - MCMR-15 - 16"

BCM Standard Midlength Enhanced Light Weight Fluted Upper Receiver Group - MCMR-15 Handguard - 16"

BCM 5.56 NATO Mid-Length BHF Barreled Upper - MCMR-15 - 16"

BCM Standard 5.56 NATO Upper Receiver Group - MCMR-15 Handguard - 20"

BCM 16" 5.56 NATO 1:7 Enhanced Light Weight Barreled Upper - 15" M-LOK MCMR Rail

BCM 18" 5.56 NATO 1:8 Stainless Steel Barreled Upper - 15" M-LOK MCMR Rail

NBS 8 Pistol 5.56 M-LOK Upper Assembly

LMT MRP Rifle Length AR-15 Quad Rail Upper Receiver

NBS 7.5 5.56 Sport DRP Pistol M-LOK Upper Assembly

NBS 10.5 5.56 Gov / SOCOM Carbine M-LOK Upper Assembly

NBS Sport 16 5.56 Gov / SOCOM Midlength M-LOK Upper Assembly

Centurion Arms C4 5.56 Billet AR-15 Upper Receiver

Centurion Arms CM4 5.56 Forged AR-15 Upper Receiver

M16A2 Assembled Upper Receiver