BARSKA Picatinny Offset Riflescope Ring, 30-mm Includes 1 ring, 1 set of screws and 4 heavy duty lock nuts Mount can be used on either side of the rail for 30mm or 1'' flashlights or lasers with a pressure switch on the back Quickly attaches and detaches from the rail with a large thumb screw 1.75-Inch Height: .88 inch Diameter: 30mm 1 Year Limited Warranty