The Midwest Industries Aimpoint QD Ring Mount is made to work and hold full size red dot sights with 30mm tube size, Aimpoint Pro, ML2, ML3 and clones. Precision machined from 6061 T6 aluminum. Hardcoat anodized for a lifetime of service Center line height of 1.690 for a lower one third sight picture Features patented Elite Defense QD lever Fully adjustable with no tools required, can be adjusted to fit rails not machined to mil-spec tolerances Extremely smooth in operation with multifaceted adjustment nut to get the exact tension required by the operator Weight 4.0 ounces 100% made in the U.S.A. with MI Lifetime Warranty Mfg: Midwest Industries, Inc.