RAM Mount 1" Ball Mount w/6.25" X 2" Rectangle Base Diamond Base [RAM-B-111-238U]1" Ball Mount with 6. 25" X 2" Rectangle Base & Diamond Base The RAM B 111 238U consists of a double socket arm, 2. 43" x 1. 31" diamond base and 6. 25" x 2" rectangle base. The diamond base contains two holes 1. 912" from center to center, positioned at both ends of the 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,