• Taper - 7-10 pitch chamfer length. • Second - 3-5 pitch chamfer length. • Plug - 1-2 pitch chamfer length. Series E500 HSS straight flute tap set is manufactured form hardy high-speed steel with a bright finish, ideal or hand or machine tapping in a wide variety of materials.
Dormer are a great quality make and this grade is perfect for steel, aluminium and brass etc. I also use them on stainless steel 303 and 304 and they are perfectly capable of cutting a thread in these materials.