Metric Coarse Spiral Point HSS - EV. Oxidised finish. Tolerance 6H. Machine Taps Spiral Point/Gun Nose With straight flutes and short fluted helix at point. Ideal for tapping through holes as swarf is directed ahead of the tap. Flutes are narrower than those of taps required to pull swarf towards the shank and act as lubricant channels, giving greater tap rigidity. Manufactured to BS 949: Part 4: 1990 and ISO 529 : 1975. High Performance Machine Taps Made from a super grade high speed steel with extra vanadium content. This has a distinct advantage with taps, by increasing wear resisting properties and extending tool life significantly. These taps are intended for general application where consistent results and improved tool life are important. Threads can be produced in a range of steels, including stainless and cast steels as well as some long chip non-ferrous materials. Oxidised Finish (Black) Special heat treated finish gives resistance to rust and reduces metal to metal fricti