The u-bolt base makes attaching to handlebars, tubing, or railing a breeze Simple to install and easy to use, the possibilities become endless Rubber ball and socket technology allows for almost infinite adjustment and perfect viewing angles High quality materials insure your device is safe, secure, and within easy reach Ram Mount's patented design also dampens shock and vibration helping to extend the life of your mobile device Included in this package is hardware that accommodates rails from 1/2" to 1.1/4" in diameter