The RAM-E-101U-D consists of a short double socket arm and two 3.68" diameter round bases that contain 4 mounting holes total. Designed into the mount is a 3.38" diameter patented rubber ball and socket system with adjustment points at both socket ends of the arm. Rubber ball and socket technology allows for almost infinite adjustment and perfect viewing angles. High quality materials insure your device is safe, secure, and within easy reach. RAM’s patented design also dampens shock and vibration helping to extend the life of your device.