RAM Marine Electronics Ball Adapter (RAM-D-115BU) (sku 54836)The RAM D 115BU, universal mounting plate, consists of a 2. 25" diameter rubber ball, connected at right angles to a flat 6. 25" x 2" rectangular plate. The plate contains different combinations of pre drilled holes which will match up to many electronic devices. HOLE PATTERN See Drawing PLATE SIZE 6. 25" x 2" BALL SOCKET SIZE D Size (2. 25") ADDITIONAL INFORMATION The 6. 25" x 2" rectangle base is a universal mounting bracket with a selection of