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. MATERIAL: 7075-T6 Aluminum COLOR: Black, DDC, or OD Green FINISH: Type-3 Hardcoat Anodize COMPATIBILITY: Mil-Spec PINS: .250 Takedown Holes Mfg: Geissele Automatics Llc