One piece offset scope mount to install magnified long riflescope of 30mm tube for easier eye relief setup. Very helpful when mounting a scope with longer eyepiece tube Ring Size: 30mm Centerline Height - 33mm Machined from extruded aluminum alloy 6061 Anodized black matte finish Clamp attachment - two hex nuts Saddle Height (from top of base rail to bottom of ring cradle): 18mm Overall height 2.30" Overall length 4.40" Offset length: 1.7"(43mm) Inner space between the rings 49mm (1.93inch) Ring width: 18mm(0.70inch) Recoil lug: 1 cross-slot screw shaft Mount weight: 4.8oz.