The Professional Spear Point HM drill bit with a diameter of 4 mm is specifically designed for drilling into hard materials such as stoneware, porcelain, hard ceramics, tiles, slate, and glass. Featuring a high-quality carbide insert, this drill bit offers high performance and durability. To achieve optimal results, the drill bit should always be used in rotary mode, with adequate cooling using water during the drilling process being essential. The drill bit is designed for a maximum speed of 1200 RPM, making it an effective tool for precise drilling in demanding materials. Ideal for professional applications, this drill bit provides the necessary robustness and efficiency to penetrate even the toughest materials.