Durable: The 40-piece thread cutting kit is made of carbon steel, ensuring durability and longevity. Multiple Applications - Ideal for threading common materials with a strength of up to approximately 900 N/mm², such as steel, cast steel, cast iron, non-ferrous metals, plastics, softwood, hardwood, and sintered wood. Multiple Options - This kit contains many different sized dies for various tapped holes, in addition to the usual metric sizes as well as many fine thread sizes. Practical and Convenient - Completely sorted in a handy storage box. The taps are supplied in a sturdy plastic case for your convenience and storage. Widely Used - This is a great tool kit, a great assortment for the service car or workshop.