The RAM-B-400-HOL-UN7BU consists of the Tough-Claw™ rail clamp base, STANDARD length double socket arm and universal spring loaded X-Grip® cradle for phones. The spring loaded X-Grip® cradle expands and contracts, allowing for a perfect custom fit of your tablet. Included are easy access grip knobs for quick insertion and release of your handheld device. The Tough-Claw™ rail clamp base is the perfect mounting base for quick and easy tool-less installation and removal on round, square, odd shaped rails and bars. The Tough-Claw™ can be clamped on rails from 0.625" - 1.5" outer diameter. Perfectly suited for mounting on the yoke of an aircraft, handlebars and seat posts of bicycles, kayak rails, roll bars and much more, the RAM® Tough-Claw™ will soon become another essential RAM® component in your collection of mounting options. 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.