The RAM-D-111-MIU consists of a 3.68" diameter round base, STANDARD LENGTH double socket arm, jam nut and 11" x 3" rectangular base. The round base contains pre-drilled holes, including two holes at 180 degrees and three holes at 120 degrees. The rectangle base 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.