The RAM-111U-DL consists of a 2.5" diameter round base that contains the universal AMPs hole pattern, 9 inch double socket arm, locking knob and 6.25" x 2" rectangle base. 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.