These forged stripped lowers are made using the most advanced aerospace manufacturing technology to produce the industries finest, forged Mil-Spec lowers. The receivers are machined on a multimillion-dollar, automated, manufacturing system that enables us to produce a product of unequaled quality and value. These forged lowers are quality made using material is 7075-T6 and are marked "Mutli-Cal" to accommodate most builds. The finish is black hard coat anodizing per Mil-8625 Type 3 class 2. Specifications and Features:Caliber: Multi