for general use - non abrasive material up to 900 N/mm² - unalloyed and low alloyed steel - for through and blind holes - for thread cutting by hand Advantages: - Pilot for exact alignment - Rougher and Finisher combined in one tool - Use in awkward places - For making new threads - For cleaning and repairing damaged threads - Hexagon Hole for Ratchet or Hexagon Keys - External Hexagon for Open-End Wrench - in high quality wooden case