Want a combo? Get started with your very own build. Our AR10 Stripped Lower Receiver is the only way to start your AR10 build. Made to Mil-Spec standards, our stripped lower receiver is second to none in quality and works with Mil-Spec AR10 parts & components. The left handed upper receiver assembly is made to mil-spec standards and includes a picatinny rail on the top, dust cover, and installed forward assist.