Geissele Automatics Super Duty Stripped AR-15 Receiver Set - Black - BLEM

Wraithworks Billet Slick Side AR-15 Upper Receiver - Black | No Forward Assist or Brass Deflector

AERO PRECISION M4E1 Multi Caliber Complete AR15 Lower Receiver w/ A2 Grip & M4 Stock - FDE

GUNTEC AR15 SLABSIDE STRIPPED BILLET UPPER RECEIVER BLACK

ONE HORSE AR15 A3 Stripped Upper Receiver Anodized

AERO PRECISION M4E1 Rifle Cmplt Lower Rcv A2 Grip No Stock Black

FAXON AR-15 X-TRA LITE RECEIVER SET OD GREEN STRIPPED

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