The RAM-B-125BU, curved extension base includes a 1" rubber ball, allowing for near-infinite adjustment and perfect viewing angles. Originally designed to position your GPS in front of the yoke on your plane, the extension plate can also be used in many other applications. The mounting section of the plate is a 2.5" square with pre-drilled holes for many different screw hole patterns, including the universal AMPS hole pattern. The connection section extends approximately 2.25" forward, at a 45 degree angle, from the center of the 1" ball and approximately 1.5'' above the 1" ball (to the bottom of the connection section of the plate).