The RAP-460Z-UN10U consists of a dual strap base with RAM Pin-Lock backing and the popular spring-loaded RAM X-Grip phone holder, featuring an 'X' design that expands and contracts to provide a perfect fit for your device - even if it's in a case. Made of high-strength composite and stainless steel, the RAM X-Grip phone holder is compatible with a wide variety of RAM double socket arms and mounting bases. This version of the RAM X-Grip fits phones ranging from 1.75" to 4.5" in width and keeps your device completely functional and accessible. Adjust the zip ties for attachment to a variety of rails, from a minimum of .5" in diameter. For outdoor applications - like being used as a bicycle phone mount - the RAM X-Grip includes a device tether that is recommended for added security and peace of mind.