Lot of 10 Ball Transfer Units Bolt Type Ball Transfer Unit (Stud Type) Lot of 10 Ball Transfer Units Bolt Type (Stud Type) Ball Transfer Unit, with one inch (1"=25.4mm) main ball, used for heavy duty loads, can be used to build a multi-direction conveyor, moving goods, feeding machines and many more, the rest is for your imagination to build a new design or create a new idea. Dimensions (mm) D D1 D2 d L2 L1 25.4mm 25mm 31mm M8x1.25 36mm 20.6mm