High hardness, rustproof, solid and durable. The advantage is opening, tapping, chamfering;-centering , do not need assistant center drilling or center punching. Suitable for drilling, tapping, cutting on soft metal, aluminum plate, iron, etc. Drilling and tapping in one, one-step processing, greatly save processing steps and time costs, working efficiency. HSS6542 (M2) is of higher hardness and more durable than the HSS4341, and is suitable for cutting the steel even the 2mm 304 steel. Color: Golden Type: Tap Drill Bit DIY Supplies: Metalworking Material: HSS+Titanium : 1/4 inch (6.35mm) hex Surface treatment:Titanium Coated Size: M3x0.5 ; M4x0.7; M5x0.8 ; M6x1 ; M8x1.25 ; M10x1.5 Suitable For: Iron, iron, steel, carbon steel You can save processing steps and time costs, efficiency a groove, within the processing thread, cutting up to exclude, and was curled applied internally threaded through holes Wear and long life Package Contents: 6 x Hex Tap Drill Bits Only the above package content, other products are not included. Note: Light and different displays may the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.