With simple structure and premium material, the grinding wheel drill bit has good sharpening effect, saving much effort. Great for fast drilling, tapping, etc. And Fast replacement composite cone, uses drill edged principle. Improve the utilization of drill bits, solve the troubles you have been buying drill bits, save time and save money. Features - Color: As Shown. - Material: Plastic, Corundum Wheel, Metal. - Size: About 17X5X1cm/6.68X1.97X0.39inch. - Adopted from premium material, it is durable and long-lasting use. - Easy to install and operate: repair the boring bit after long-term use - Fast replacement composite cone, uses drill edged principle. - Improve the utilization of drill bits, solve the troubles you have been buying drill bits, save time and save money. - Suitable for iron bit, motor bit replacement