7/8" inch (22.23mm) Ball Bearing with 5/16" inch (7.94mm) diameter integrated 1 1/4" inch (31.75mm) Long Axle, Pin Diameter is 5/16" inch, Bearing Outer diameter is 7/8" Inch (22.23mm), and Width of the assembly is 1 1/4" Inch (31.75mm Long), Bearing is made of Chrome Steel.