20mm Diamond Donut Bur – 400 Grit, 5pcs Rotary Tool Grinding Bits for Glass, Stone & Ceramic sintered diamond burs the blade must be used

the blade must be used with water or oil-based lubrication to prevent overheating and extend its life

and tight radii—ideal for cabochon shaping

fast-cutting bits with brass or chrome-hardened steel cores for rapid material removal

this system supports grinding

precision-crafted tool is designed for use with expanding drum belts and standard sanding sleeves on lapidary wheel machines

20mm Diamond Donut Bur – 400 Grit, 5pcs Rotary Tool Grinding Bits for Glass, Stone & Ceramic sintered diamond burs the blade must be usedDiamond Drill Bits are precision tools for fine detailing and material processing. Discover the versatility of diamond drill bits, designed with durable diamond grit for aggressive cutting, precise shaping, and long lasting performance. Available in multiple gritscoarse (40,60,80,120) for rapid material removal, and fine(240,600,1200) for detailed engraving and polishing. These tools suit lapidary artists, jewelers, sculptors, and precision craftsmen.