Mounts from American Defense MFG LLC, with the patented Auto Lock Lever ADM The AD-68C Cantilever features an lower 1/3 co-witness (co-witness near bottom third of optic) when used on an AR15, M16, M4 flat top with Mil-Spec size iron sights. The mounts are billet machined from aircraft quality 6061 T6 aluminum. Products are hard coat anodized for a lifetime of superior performance. Mounts are fully adjustable to fit in spec and out of spec 1913 picatinny rails. Mounts feature a large adjustable lever that incorporates the patented Auto Lock feature that will lock the lever in the closed position. The Auto Lock Lever system features a large clamping surface to insure maximum contact with the rail. The Auto Lock Lever does not require tools for adjustments. All American Defense Mfg LLC products feature a lifetime warranty. Made with pride in the U.S.A.