The RAM-B-121BAU, yoke clamp mount with 1/4″-20 thread, will fit rails from 0.625″ to 1.25″ in diameter. The 1″ rubber ball is set at a right angle to the plane of the mount, so when connected to a rail, the ball sits parallel to the rail.
Clamp Base Dimensions:
Accommodates rails from 0.625″ to 1.25″ in diameter
High Strength Composite and Powder Coated Marine Grade Aluminum
1″ Rubber „B” Ball Size
The „U” in the part number reflects product packaged in poly bag.