Premium REZ soft diamond wheels achieve superior performance, offering high quality surface finish. Premium REZ diamond standard soft wheels perfectly perform polishing, sanding, shaping, cabbing and grinding operations, used correctly, last very long. Commercial grade wheels. Work with most stones, gemstones, ceramics, glass. The bore diameter is 1". Wheels include reducing spacers to reduce bore to fit shafts with diameter 3/4 inch, 5/8 inch, 1/2 inch. Produced with plastic core to keep the wheel light. There is flexible foam padding on the outside ring of the plastic body, so when working stones can be pushed to the wheel with the resistance. The outside of the wheel is covered with resin with diamond particles in the layer. Premium REZ wheels require break-in period. So break-in process must be performed before using the wheels. Instructions how to do it are included in the box, or you just can send us a message and we will send you the instructions. It is quick and easy process to do. Please choose the correct grit size ordering the wheel. Will work with most cabbing machines like: Covington, Cab King, Diamond Pacific, Lortone and others. Most common sizes are listed in our other listings, other sizes available upon request. Wheels are ready to use at once taken out of the box, no need to break them in before working. Very good for lapidary use and other similar grinding operations. In other listings we also offer Premium REZ wheels in 8" diameter, Standard soft wheels outside diameters 6" and 8". Hard electroplated wheels are offered in diameters 6" or 8", can have flat shape, convex or textured plating.