The RAM-B-166-UN11U consists of a 8.38cm (3.3") diameter suction cup twist lock base, double socket arm, round base adapter and universal X-Grip clamping cradle for 30.48cm (12") -33.02cm (13") tablets. The suction cup base is designed to have a strong hold on glass and non-porous plastic surfaces. The mount is designed with a RAM 2.54cm (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 X-Grip clamping cradle consists of a composite spring loaded cradle, expandable grip arms and additional bottom support keeper. Included are extra easy access grip knobs, located on the back of the cradle for quick release of your tablet. The X-Grip clamping cradle expands and contracts for perfect fit of most 30.48cm (12") tablets with or without sleeves, as well as some smaller tablets. Please verify dimensions of your tablet below for compatibility with the X-Grip. The X-Grip 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.