6-piece tap drill set made of high-strength HSS steel with a titanium coating. Drill bits allow you to drill holes and thread at the same time. They are easy to use, making them perfect for both the workshop and the garage. It is recommended to drill at a low speed and use coolant when working. Product features : HSS steel coated with titanium Hex Socket 1/4 inch (6.35 mm) Thread sizes: M3, M4, M5, M6, M8, M10 Drills in the set : M3x 0.5: total length: 55mm, helix length: 24mm, drill diameter: 2.5mm M4x 0.7: Total Length: 54mm, Helix Length: 24mm, Drill Diameter: 3.3mm M5x 0.8: Total Length: 58mm, Helix Length: 28mm, Drill Diameter: 4.2mm M6x 1.0: Total Length: 58mm, Helix Length: 28mm, Drill Diameter: 5.0mm M8x 1.25: Total Length: 59mm, Helix Length: 18mm, Drill Diameter: 6.8mm M10x 1.5: Total Length: 59mm, Helix Length: 20mm, Drill Diameter: 8.5mm