Stripped, semi-auto, lower receiver delivers custom shop quality without the typical custom shop price. Perfect platform for building the ultimate, mission-specific, AR-15 rifle or carbine. Made from a high-strength, 7075 T6 aluminum forging for reliable performance and outstanding durability. Mil-Spec, hard anodized finish adds extra strength to the receiver walls and delivers superior abrasion-resistance for rugged field use. Precision-machined to ensure drop-in installation of Mil-Spec, aftermarket components. Mfg: Anderson Manufacturing SPECS: Fits - Standard AR-15 components. Receiver is identified as "MULTI CAL"