Spring-loaded holder features adjustable side supports that provide a secure fit for a variety of large phones and other devices; easily insert and remove your phone with one hand. Includes U-bolt base that accommodates rails from 0.5" to 1.25" diameter and a short length, B-size RAM® double socket arm. Ball and socket technology allows for near-infinite adjustability. Made of powder-coated, marine-grade aluminum and high-strength composite for durability and reliability in the most demanding environments.