This robust 6-screw Tactical 30mm Ring is perfect for mounting red dot optics, magnifiers and other accessories with 30mm tube diameters to your Picatinny rail. When using this ring to mount a conventional riflescope, we strongly recommend lapping the rings for a proper and secure fit for your optic. Available Vortex Tactical 30mm Rings MPN Height Optical Centerline TRL Low 0.83" TRM Medium 0.97" TRH High 1.18" TRXH Extra-High Lower 1/3 1.57" TRXHAC Extra-High Absolute 1.46" Learn More About Vortex Tactical Series Rings Vortex Tactical 30 mm Ring (Sold individually) Extra-High, Absolute Co-Witness for AR15 (1.46 Inch / 37.0 mm) TRXHAC