RAM 1″ Diameter Ball Mount with 6.25″ X 2″ Rectangle Base & 2.5″ Round Base The RAM-B-111U, powder coated marine grade aluminum mount, consists of a double socket arm mount, one 2.5″ diameter round base with 1″ rubber ball and flat 6.25″ x 2″ rectangular plate. The plate contains different combinations of pre-drilled holes which will match up to many electronic devices and mounts, including Marine GPS, CB Radios, Ham Radios, Gimbal Brackets and more. Rubber ball, socket technology dampens shock and vibration, as well as allows for almost infinite adjustment, perfect viewing angles. For most applications, mount will support up to three pounds. Material: Powder Coated Marine Grade Aluminum Ball Size: 1″ Rubber Ball “B” Size Note: The “U” in the part number reflects product packaged in poly bag. For mounting a GPS puck antenna to this mount, RAM recommends the RAM-338U