Check the listing for details. RAM-201U RAM Mounts Medium Length Double Socket Arm for C Size 1.5-Inch Balls. Condition: Used. Listed at 18.99 USD. FEATURESMedium length double socket arm has an overall length of 5.69" and a socket-to-socket length of 4.66"Attaches to any C size RAM® ball component, including mounting bases and device holders; double ball and socket technology allows for near-infinite adjustability of your RAM® mounting systemMade of powder-coated, marine-grade aluminum for durability and reliability in the most demanding environmentsThe RAM-201U consists of a medium length double socket arm that accommodates 1.5" C size ball bases, device holders, and adapters. A single spring inside the arm keeps the socket open, and allows you to insert the ball into the socket connection. This arm has an overall length of 5.69". The easy to adjust knob allows for near-infinite adjustability.