SBT-1-1/2 CS Stud Mounted Ball Transfer Unit 1-1/2" Main Ball 3/8"-16 Threaded stem Proudly made in the USA SBT-1-1/2 CS Stud Mounted Ball Transfer Unit, Main Ball is 1 1/2" Inch, 1-1/2" Main ball rotates on (90) 3/16" support balls, SBT-1-1/2 CS stud-mounted ball transfer is a heavy duty ball transfer unit, capable of supporting as many as 250 pounds (per unit). SBT-1-1/2 CS features a 1 and 1/2 inch ball bearing resting on 90 individual support bearings and is ideal for most industrial transfer applications. SBT-1-1/2 CS ball transfer can also be used in a variety of non-industrial applications, including retail store displays and airport luggage transfers.