RAM Drill-Down Double Ball Mount with Universal Action Camera Adapter (RAM-B-138-A-GOP1U) (sku 51147)RAM Drill Down Double Ball Mount with Universal Action Camera Adapter (RAM B 138 A GOP1U) The RAM B 138 A GOP1U consists of a 2. 5" diameter round base with the universal AMPS hole pattern, SHORT size double socket arm and 1" diameter ball with custom GoPro Hero adapter. 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