22mm Fine Grit Nickel Electroplated Diamond Donut Burs Point Bits

Electroplated carving points  can be used on many materials such as glass, stone, hard wood, ceramic, shell and porcelain. To get the best life and usage out of your burrs use with a little water before or during use.Nickel electroplated diamond grit 80# 240# and 320# donuts burs. Designed for to grind simple and quick a donut. On the top are holes which allows water flow trough to keep the working surface well and properly lubricated. Step one, drill the middle hole, step 2 use the donuts tool, the middle hole who you drill before will you guide.Shank size 6mm, best in use with drill press.