SPR Scope Mount Features The Ultralight 1 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. SPR Scope Mount Specifications Aero Precision SPR Scope Mount Ultralight 1 Anodized Black