ITEM NAME:20pcs/Bag Shank Diamond Grinding Burr Drill Bits Sets for Dremel Tool Rotary Product Description 20Pcs 120 Grit Diamond Burr Set Drill Bits Set for Dremel Tool Rotary Grinding Specification: 100% Brand new and high quality. Material: Alloy + Diamond (120 × fine sand) Color: As pictures shown Quantity: 20pcs/Bag Handle Diameter: Approx.3mm Head Diameter: Approx.6mm Conversion: 1mm=0.039inch, 1inch=25.4mm Features: Thick, durable and high-strength diamond, made of artificial diamond and electroplated with high-strength diamond. The rod is made of alloy material with high wear resistance and hardness, which is more durable. Suitable for grinding, engraving, cutting lines, polished, hollow, jade carving, glass engraving etc. Mainly used to polish glass, jade, repair abrasive and other hard objects. Ideal for hanging mill, electric mill, engraving machines, electric machinery and supporting assembly. A a deal correction tool for processing of various molds, car.Suitable for grinding, engraving, cutting lines, polished, hollow, jade carving, glass engraving etc. 20pcs/Bag Diamond Grinding Head. Thick, durable and high-strength diamond, made of artificial diamond and electroplated with high-strength diamond.