The RAM-B-108BU consists of a B size 1" rubber ball connected at a right angle to a V-shaped base, and accommodates rails from 1" to 2.1" in diameter. To mount the RAM-B-108BU base, place the saddle-shaped plate on the rail and then wrap the metal clamp strap around the rail and plate. Tighten the knob on the metal strap with a screwdriver until it has a firm hold on the rail. The RAM-B-108BU is an alternative mounting base for Beechcraft airplanes with a throw over yoke."