American Tactical Milsport 5.56 7.5" M-LOK Upper Receiver

AERO PRECISION AR15 5.56 NATO / 223 Rem 20" Complete Upper Receiver w/ Carry Handle | Black

CMMG 55BB40BMB Resolute MK4 5.56x45mm NATO 16.10", Midnight Bronze, M-LOK Free-Float Handguard for AR-Platform (No BCG or Charging Handle)

AERO PRECISION M4E1 Threaded Complete Upper 16" 5.56 Barrel w/ 15" M-LOK ATLAS R-ONE Handguard - BLK

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

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

VKTR Industries VK-1 5.56x45mm 16" 1:7 M-LOK Rail w/ BCG & CH, Black - V-4027-3410-001-RP

CMMG DISSENT Mk4 AR-15 6.5" CM .300 BLK Upper Receiver w/ 5.5" M-LOK Handguard-Midnight Bronze