Diamond coating maximizes performance and maintains a sharper cutting edge. Nickel-plated surfaces extend service life and enhance corrosion resistance. Suitable for precise drilling in glass, ceramics, porcelain, ceramic tiles, porcelain tiles, etc. Not suitable for drilling tempered glass, plastic, or wood. ----------------------------------------------- We have many other various products available, so #Miyako's Listings ← Tap to take a look ♡ #Miyako's Tools are here ♡ ＊Instant purchase welcome ＊Welcome bulk purchases, feel free to comment ＊Free shipping! ・Please understand that items are stored at home and will be shipped in simple packaging. There may be cases where we ship items without their boxes. Thank you for your understanding. ・Please check the actual photos for the condition of the product. ----------------------------------------------- Glass Hole Saw 22mm Diamond Drill Bit Silver Tone Carbon Steel Diamond Particles 10 Pieces 42-14.20-18-9