Electrolytically coated diamond drill bits for use with an electric drill without impact. The diamond quality allows for drilling holes in stoneware, porcelain stoneware, granite, marble, and glass. Ideal for finishing bathrooms and adding decorative elements to any ceramic surface. Always use with the Easy Gres guide, which allows for proper guidance and cooling, guaranteeing accuracy and a good finish. Average durability: up to 15 holes, depending on the material being drilled. Steel body, electroplated diamond tip. A hole in the side surface of the drill bit allows for better cooling and removal of drilling debris. Recommended operating speed is 400-1000 rpm, depending on the material. Do not exceed the recommended speed and do not apply excessive pressure when drilling. This will ensure the best drilling results and extend the life of the drill bit.