AERO PRECISION M4E1 Carbine Complete AR15 Lower Receiver w/ A2 Grip - Black

Timber Creek Outdoors AR Lower Parts Kit for AR-15, Robin's Egg Blue - AR LPK RE

AERO PRECISION M5 308 Win Assembled Upper Receiver | OD Green

AERO PRECISION M5 308 Assembled Upper Receiver | Kodiak Brown Anodized

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

AERO PRECISION M4E1 Stripped Lower Receiver | Kodiak Brown Anodized

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

BATTLE ARMS Authority ELite Upper Recv 5.56 10.5" AR-15 Gray