1 1/8" inch (28.58mm) Ball Bearing with 3/8" inch (9.53mm) diameter integrated 1 1/4" inch (25.4mm) Long Axle, Pin Diameter is 3/8" inch, Bearing Outer diameter is 1 1/8" Inch (28.58mm), and Width of the assembly is 1 1/4" Inch (31.75mm Long), Bearing is made of Chrome Steel.