Diamond Hole Saw Drill BitThe diamond hole saw drill bit is made of carbon steel, with a neat and clean opening, no broken edges. Low cutting resistance, drilling stable and will not break the boundary. Good DesignThe center guide holes and side holes help to remove the waste material easily; And have gold colors to avoid rusting and improve surface corrosion resistance. Application It can be used for drilling ceramic tile, marble, glass, granite, concrete and other hard materials. Works with all electric drills and impact drills. Please NoteWhen cutting hard materials, it is important to ensure the cutter is kept cool to avoid damaging the material being drilled and premature wear of the cutter. When drilling becomes water needed for lubrication, which can extend the life of the drill. Buy with Confidence We offer TWO YEARS" warranty on the hole saw. For questions, please contact us. We will try our best to solve it for you. (Please clamp the shaft correctly and take the necessary protective measures for the woodworking