19 Piece Faithfull Cobalt HSS Drill Set for heavy-duty industrial work in: Alloy steels, carbon steels, cast iron, hardened alloy steels, stainless steels, high temperature alloys, Titanium alloy, high strength steel and carbon fibre composite materials. Manufactured from M35 HSSE grade steel with a 5% cobalt content for increased heat resistance and cutting performance. All bits are fully ground, with sizes over 2.5mm featuring a 135 non-slip split point for precise centring. Bits are produced in accordance to DIN 388 for high precision tolerances and geometric accuracy.Cobalt bits cut faster and last longer and are suitable for heavy-duty industrial work in: Alloy steels, carbon steels, cast iron, hardened alloy steels, stainless steels, high temperature alloys, Titanium alloy, high strength steel and carbon fibre composite materials. Supplied in a robust plastic case clearly marked with each drill size, which secures and protects the drills when in storage. Sizes: 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, and 10mm