The RAM-B-202-379-M616U consists of a 2.5" diameter round base with the universal AMPS hole pattern, STANDARD size double socket arm and 1" diameter ball, containing a M6 x 30 SS HEX head bolt. 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 RAM-B-202-379-M616 reduces the mounting footprint, compared to old dragonfly units that contain a large neck. This mount allows for a seamless marriage of RAM components into your Raymarine system, opening up the ball and socket system and all of our mounting options to you.