Zinc coated U-bolt base, double socket arm and universak 1/4"-20 thread, centered on a 2.5" diameter plate The male 1/4" long, 1/4"-20 thread in the middle of the 2.5" diameter plate will connect to the standard female thread foundat the bottom of most still and video cameras Includes hardware that will accommodate rails from 0.50" to 1.25" in diameter Base includes black cover caps to be placed over the exposed ends of the U-bolt A composite rail adapter can narrow the rail to a minimum width if 0.5" Mount designed with a RAM 1" diameter patented rubber ball and socket system that has adjustment points at both ends of the double socket arm