1. Smooth chip removal and high hole opening efficiency ensure faster and more aggressive drilling for quicker project completion. 2. Designed with an M14 thread for stable connections to various drilling equipment, simplifying tool selection and use. 3. Designed for prolonged use in masonry drilling applications. 4. Wide diameter range: available in sizes from 20mm to 68mm, catering to diverse drilling needs in various materials. 5. Wide application range: versatile for drilling through tile, ceramic, marble, and stone, suitable for a variety of DIY and professional applications. Color: Black Material: 45# steel + secondary emery Package Contents: 1 set * Diamond Dry Drilling Core Bits Only the above package content is included; other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture to vary slightly from the real thing. Measurement may vary by +/- 1-3 cm.