Our Ultralight 30mm SPR Scope Mount features a rear ring that is pushed forward 2", resulting in better eye relief. This scope mount is designed to fit AR type upper receivers with Mil-Spec 1913 Picatinny rails and features a cross-slot keyway that offers excellent recoil protection.Our Ultralight Scope Mounts free you from unnecessary bulk, providing one of the lightest mounts in the industry.