The RAM-D-111U consists of a 3.68″ diameter round base STANDARD length double socket arm and 11″ x 3″ rectangular plate. The round base contains pre-drilled holes including two holes at 180 degrees and three holes at 120 degrees. The rectangle plate contains different combinations of pre-drilled holes which will match up to many electronic devices and mounts including Marine GPS CB Radios Ham Radios Gimbal Brackets and more.