The B size 1'' ball double socket arm made of high strength composite PA66+GF30% for durability and reliability in the most demanding environments With an overall length of 3.54'' ( 90mm ) Compatible with RAM Mounts & BRCOVAN any B size 1'' ball components, including mounting bases and device holders. 1" diameter B size sockets fit for all 1'' diameter ball joints The double socket arm (medium arm) made of high strength composite PA66+GF30%. Compatible with RAM Mounts and BRCOVAN B Size 1'' ball components & bike motorcycle phone mount holder with 1'' Ball Adapter. With an overall length of 3.54'' ( 90mm ). PACK of two.