The clamp mount will grip to a round rail or flat edge lip from 0.625" to a maximum of 1.25". The 1" rubber ball is positioned at a right angle to the plane of the mount so when connected to a rail, the ball sits parallel to the rail. The clamp mount can be used as a universal mounting solution for microphone stands, guitar stands and flat edge lips.  This mount is constructed of marine grade powder coated metal.  The cradle is constructed of heavy composite.