This RAM Ball Adapter with AMPS Plate from RAM MOUNTS consists of a B-size 1' diameter rubber ball connected to a 1.7 x 2' base. The base has four pre-drilled holes at each corner, using the universal AMPS hole pattern. The included B size 1' RAM rubber ball allows connection to any B-sized RAM double socket arm; ball and socket technology allows for near-infinite adjustability. The adapter is made from powder-coated, marine-grade aluminum for durability and reliability in the most demanding environments.