The RAP-401-202U consists of a large Tough-Claw base, a double socket arm, and a round base adapter. The RAM Tough-Claw is the perfect mounting base for quick and easy tool-less installation and removal on round, square, and oddly shaped rails and bars. The Tough-Claw can be clamped on rails with an outer diameter of 1" to 2.25". The round base adapter features the industry standard universal AMPS hole pattern, which connects to a wide variety of RAM Mount and third-party cradles. The mount is designed with a RAM 1.5" diameter patented rubber ball and socket system that has adjustment points at both ends of the double socket arm, allowing for almost infinite adjustment and perfect viewing angles. Clamping range for rail/tube surfaces is 1" to 2.25" and for flat surfaces is 0" to 2.2".