Anderson B2-K401-A0B1: Anderson Complete Open Trigger Assembled Lower. This includes Lower Parts Kit installed, but does not include the buffer tube assembly or stock / pistol brace.
The perfect platform for building the ultimate, mission-specific, AR-15 rifle, carbine or pistol build. 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. This complete lower utilizes the Anderson Manuf. lower receiver with an Anderson Lower Parts Kit and is already assembled