[SIZE] - 7mm diameter, 200mm length twist drill bit with 7mm shank.. [MATERIAL] - Diamond coated high speed steel is made by spiral technology, has both toughness and hardness, is not easy to break. The drill bit is sharp, and is easy for chip removal.. [APPLICABLE MACHINE] - Widely used in rotary tool such as hand drills, drill press, flex shafts, bench drill and hanging mill.. [APPLICATION] - Suitable for drilling small holes on glass, metal, sea shells, jade, pearls, marble, stones, drywall and son on. Due to the different hardness of the material, the effect is also different.. [NOTICE] - When drilling, it is necessary to add cutting fluid in time to lubricate and cool down, which can get a better drilling hole wall, extends the service life and drilling accuracy..
