47.6mm Conveyor Bearings for Rollers D1DdHBLoading(lb) 50.7mm47.6mm12mm18mm13mm580 One slow speed unground flanged ball bearings for use with the conveyor rollers (pipes/cylinders), inner diameter bore=12mm, outer diameter=47.6mm, the mechanical drawing and the table above shows all the dimensions, the table shows also the load capacity, good luck building your conveyor system.