Luth-ar LRPK-BLDR Lower Receiver Builder Kit AR-15 .223 Rem/5.56 NATO Black
No MIM here. Luth-AR produces only American-made lower parts kits with components investment cast or machined to MILSPEC drawings, materials, and heat treat. Springs are made from certified 174 SST or MILSPEC steel wire, providing traceable, high-quality components for the AR platform.