The Light Weight double 1.75″ Rubber Suction Cup Base has a standard RAM double hole diamond plate end. The suction cup is designed to have an light to medium hold on any smooth non-porous surface, but for best result, mount the suction cup on a glass surface. The diamond plate end has two holes 1.912″ from ceneter to center. This will connect to the RAP-B-238 Diamond Plates Series or directly to the back of the RAM Plastic HOL Cradles. Included with the Suction Cup Base are two connection screws. This suction base DOES NOT have a RAM 1″ rubber connection ball.