The best 80% receiver in production! Each lower is fully CNC machined from a 15 lb 7075-T6 aluminum billet on a CNC horizontal machining center at an ISO 9001 certified factory. No highly stressed and inaccurate forgings are used. Every surface of the lowers is machined. The lower maintains close tolerances on all features to ensure a perfect part every time. The magazine well is EDM machined out to ensure no mismatch from milling and broaching. The magazine well also had a much larger flare than a typical forged receiver for quicker more reliable reloading. Finally, the lower receivers are tested for dimensional accuracy on a Zeiss UPMC Ultra CMM The quality and attention to detail are second to none.