RAM Mount 1" Diameter Ball Mount w/Short Double Socket Arm, 6.25" x 2" Rectangle Base & 2.5" Round Base (AMPS Pattern) [RAM-B-111U-A]1" Diameter Ball Mount w Short Double Socket Arm, 6. 25" x 2" Rectangle Base & 2. 5" Round Base (AMPS Pattern) The RAM B 111U A consists of a short double socket arm, 2. 5" diameter round base and 6. 25" x 2" rectangle base. The round base contains pre drilled holes, including the universal AMPS hole pattern. The rectangle base contains different combinations of pre drilled holes which will match up to many electronic devices and mounts, including