【EXQUISITE CRAFTSMANSHIP】Our diamond drill bits are made of industrial-grade carbon steel, with a nickel-plated coating to resist corrosion; fine workmanship, super wear-resistant and sharp. 【HIGH QUALITY DRILL BITS】Each hole is smooth and precise surface treatment, and the thick diamond coating on the top can provide excellent cutting force to achieve maximum drilling effect. 【LARGE CLEARANCE HOLES】These glass hole saws are arranged along the drill bit to facilitate the evacuation of chips and other particles when entering and drilling cooling water. Make the drilling process easier. 【WIDELY USED】This glass drill bit set contains 15 different drill bits to meet various needs. It is used for drilling hard surfaces such as glass, wood, ceramic tile bottles, block pots, ceramic, slate, granite pumice, etc. 【NOTE】When cutting hard materials, be sure to keep the tool cool to avoid damage to the material being drilled and premature wear of the tool; water lubrication is required when