The Super Duty Receiver Set includes a Geissele Super Duty stripped lower and a Geissele Stripped Upper receiver. This high quality receiver set is precision machined from 7075-T6 aluminum and finished in durable Type 3 hardcoat anodize. With laser engraved T-marks and SAFE/FIRE markings, this mil-spec conforming Geissele Super Duty Receiver Set is the perfect start for your high-quality dream build. LOWER SPECS: MATERIAL: 7075-T6 COLOR: Black, DDC, or OD Green FINISH: Type-3 Hardcoat Anodize COMPATIBILITY: Mil-Spec PINS: .250 Takedown Holes UPPER SPECS: MATERIAL: 7075-T6 COLOR: Black, DDC, or OD Green FINISH: Type-3 Hardcoat A Mfg: Geissele Automatics