The yoke clamp base will fit rails in diameter from 0.625" to a maximum of 1.25". The 1" rubber ball is at a right angle to the plane of the mount; when connected to a rail, the ball sits parallel to the rail.
Material: High Strength Composite and Powder Coated Marine Grade Aluminum
Ball Size: 1" Rubber "B" Ball Size
Note: The "U" in the part number reflects product packaged in poly bag.
Weight: 0.35 lbs.
Clamp Base Dimensions: Accommodates rails from 0.625" to 1.25" in diameter