Check the listing for details. RAM Mount Garmin G-Ball Adapter Surface Drill-Down Mount RAM-B-138-GA22U. Condition: New. Listed at 35.99 USD. Manufacturer Description The RAM-B-138-GA22 RAM Mount Marine Grade Aluminum Round Screw Down Base Plate Mount consists of the 1 inch diameter ball and socket system with a RAM Plastic Cradle for the Garmin GPS G-Ball Socket. Mount Base Design: The RAM-B-202 RAM Mount Marine Grade Aluminum Screw Down Plate has a 1.0 inch diameter Rubber Ball connected at right angles to a 2.5 inch diameter Plate. The plate has pre-drilled holes in the base plate, including the universal AMPS hole pattern. Mount Base Mounting Solutions: Mounting hardware is NOT included with the purchase of the RAM-B-202. Mount Arm Design: The RAM Mount Dual Socket Arm (RAM-B-201) is a B Size 1 inch Ball Dual Socket Arm, made of Marine Grade Aluminum. The arm is 3 inches long between socket centers and is finished with a Black Powder Coating. The side of the arm includes a tightening knob which allows you to open and close the socket ends.