The Geissele Super Duty Stripped Lower, made from a 7075 T6 aluminum forging, is precision machined and quality assured to the mil-spec standard at the Geissele facility. The Super Duty stripped lower is the heart of your next build, ready to accept your favorite components to make your next AR15-pattern rifle truly your own. Blem receivers have cosmetic or machining imperfections that are 100% functional. Imperfections includes dings, scratches, machine marks, or mismatched color tones. MATERIAL: 7075-T6 COLOR: Black or DDC FINISH: Type-3 Hardcoat Anodize COMPATIBILITY: Mil-Spec DESIGNATION: CAL 5.56MM INDICATORS: Safe/Fire Mfg: Geissele Automatics