Expo Arms Barreled AR-15 Upper Receiver - 5.56 - 16" - Quad Rail

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

Larue Tactical LT1555616QUADLC LT15 Quad Rail 5.56 10+1 16" Stealth Barrel Black Right Hand

Larue Tactical LT1555620QUAD LT15 Quad Rail 5.56 30+1 20" Stealth Barrel Black Right Hand

Bushmaster AR-15 Complete Upper Minimalist SD 556 Nato AR15 16" 90025

BUSHMASTER M4 Type Patrolman Flat Top A4 Upper 5.56 16" Black

BUSHMASTER QRC Upper 5.56 NATO 16" - Black

TacFire AR-15 .223 / 5.56 Unassembled Upper Receiver Kit - 10"