"The RAM-B-166U consists of a 3.3"" diameter suction cup twist lock base, STANDARD length double socket arm and diamond base adapter. The suction cup base is designed to have a strong hold on glass and non-porous plastic surfaces, including RAM adhesive disks. The mount is designed with a RAM 1"" diameter patented rubber ball and socket system that has adjustment points at both ends of the double socket arm; this allowing for almost infinite adjustment and perfect viewing angles. The hole pattern found on the diamond base adapter will connect to most RAM cradles."