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. Height: Medium (0.97" / 24.6mm) Outside Diameter: 2.4 - 2.6 " / 62-66mm Weight: 6.7 oz