The RAM-111U-B consists of a short double socket arm, 2.5" diameter round base, and 6.25" x 2" rectangle base. The round base includes a 1.5" C size rubber ball and contains pre-drilled holes, including the universal AMPS hole pattern. The rectangle base also includes a 1.5" C size rubber ball and contains a variety of pre-drilled holes that are compatible with several marine electronic devices, including fishfinders and chartplotters.