Material: Diamond holesaw drill is made of diamond sand material, which is sturdy and smooth, can be used for a long timeUnique Design: The drill holesaw is designed with a serrated cutting edge, which can make a sharp and smooth cutFeature: Features vacuum brazed technology with high diamond concentration for faster cutting speed. Easy to use and user-friendly, providing neat, smooth drilling without any chipping or rough edgesPractical: The front and rear double chip removal holes are designed for smoother drilling, lower cutting resistance overall, better chip removal, and faster drillingApplication: Diamond core bits to drill holes in porcelain, cement, bathroom tiles, marble, granite, stone, masonry, brick with ease Specification: Material: Diamond Sand Size Chart: 40mm: 6cmx6.4cm/2.36inchx2.52inch 45mm: 6.5cmx6.4cm/2.56inchx2.52inch 50mm: 7cmx6.4cm/2.76inchx2.52inch Package Includes: 1 Piece Diamond Hole Drill Note: The product is installed in a professional drill or electric drill, bench drill. you need to add water cooling holes during operation.