3/8" Inch Ball Bearing with 1/4" diameter integrated 1/4" Inch (6.35mm) Pin Diameter 1/4" x 3/8" x 7/8" Inch 3/8" inch (9.53mm) Ball Bearing with 1/4" inch (6.35mm) diameter integrated 7/8" inch (22.23mm) Long Axle, Pin Diameter is 1/4" inch, Bearing Outer diameter is 3/8" Inch (9.53mm), and Width of the assembly is 7/8" Inch (22.23mm Long), Bearing is made of Chrome Steel.