Build your ideal AR with the Luth-AR Lower Parts Kit Builder. This high-quality kit features American-made parts, ensuring durability and performance. Each component is crafted using investment casting or precision machining to Mil-Spec standards, guaranteeing reliability for your .223 REM/5.56 NATO builds. The kit includes springs made from a combination of 17-4 SST and Mil-Spec steel wire, all certified for safety and quality. Upgrade your firearm with confidence using the Luth-AR Lower Parts Kit.