【9PCS DRILL BIT SETS】5mm. 6mm. 6mm.8mm. 8mm.10mm.12mm.14mm.16mm*160mm; The drilling depth is 100mm. With this, you can drill all common dowel holes. (For your machine and personal safety, it is not recommended to use a three-claw impact drill) 【CARBIDE BITS】: The drill bit set is made of high-quality carbide steel, durable and rust-resistant. The tungsten carbide-tipped drill head is harder, stronger and more resistant to extreme loads; high-density drilling and fast waste removal 【X-HEAD】: It features an innovative X-shaped geometry with a unique cross-flute design for optimal disassembly and ease of use. Fully hardened drill bit with a double flute spiral for efficient waste removal. 【2-HOLE SHANK】Round shank, 2-hole drill bit, regular drill bits in individual red case for concrete, granite, stone. It ensures optimal dust and debris removal via rounded spiral geometry, more efficiently. 【APPLICATION】: Suitable for drilling holes in concrete, ceramic tiles, stone, wood, aluminum,