Wheelchair Rail - Tube Mount with Extension and Double Socket Swivel Arm to Camera - Camcorder Base (sku 21714)Wheelchair Rail and Tube Mount with Extension and Double Socket Swivel Arm to Camera Camcorder Base. This Mount features a tool less Small Tough Claw base with 1" rubber ball, a Long Double Socket Arm, a Double 1" Ball Adapter, a Double Socket Swivel Arm with central hinge together with a 1" rubber ball connected to a round plate with 1 4" 20 camera thread. The round plate provides extra support and stability for cameras that rest on top of it. The