SMBT-5/8 CS/SS Solid Machined Ball Transfer Unit 5/8" Main Ball Proudly made in the USA SMBT-5/8 CS/SS Solid Machined Ball Transfer Unit, Main Ball is 5/8" Inch, 5/8" Main ball rotates on 3/32" support balls, SMBT-5/8 CS/SS stud-mounted ball transfer is a heavy duty ball transfer unit, capable of supporting as many as 33 pounds (per unit). SMBT-5/8 CS/SS features a 5/8" inch ball bearing resting on 3/32 inch individual support bearings, making it ideal for most industrial transfer applications. SMBT-5/8 CS/SS ball transfer is also useful for a number of different applications where traditional wheel casters are used, including retail store displays.