General description High-quality 7-piece carbide stone drill set designed for drilling into a variety of materials including porcelain, tiles, concrete, brick walls, glass, mirrors, plastic, masonry, and wood. The set includes drill bits in seven different sizes: 3mm, 4mm, 5mm, 6mm, 8mm, 10mm, and 12mm, making it suitable for various drilling tasks. Technical specifications Material: Carbide alloy head Sizes: 3mm, 4mm, 5mm, 6mm, 8mm, 10mm, 12mm Shank type: 3-flat shank Usage Designed for drilling into hard materials such as concrete, brick walls, glass, tile, marble, and granite. For optimal performance when drilling hard materials, use water for lubrication. Other information U-shaped slot design for fast dust removal and smoother drilling. Rotating thread cutting for efficient chip removal. Stable operation with a firm grip to prevent slipping or scratching. First-class performance with sharp tips for clean and smooth openings.