The RAM-B-138-UN8 consists of a 2.5" diameter round base with the universal AMPS hole pattern, double socket arm and universal X-Gripclamping cradle for 7"-8" tablets. 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 spring loaded X-Grip cradle expands and contracts, allowing for a perfect custom fit of your 7"-8" tablet. Included are extra easy access grip knobs, located on the back of the cradle for quick release of your tablet. The X-Grip includes a device tether recommended for outdoor applications. The cradle is compatible with handheld devices that will fit the dimensions listed below. It is important to verify the dimensions of your handheld device with a case/sleeve/skin when determining the overall size.