This mount will suit bars that are between 1 1/8" and 1 1/2" (2.86cm and 3.81cm) in diameter. It includes sizing inserts that help provide a snug fit and protect your bar, as well as nylon-insert locknuts to prevent loosening during high vibration. 

It has a 1" ball attached.

• Mounting Base Dimensions: Accommodates rails 1 1/8" to 1 1/2" (2.86cm to 3.81cm) in diameter
• Material: Powder Coated Marine Grade Aluminium
• Ball Size: 1" Rubber Ball "B" Size

Note: The "U" in the part number reflects product packaged in poly bag.