This comprehensive set includes tin-coated HSS jobber drills and a versatile 4-25mm step drill, designed to cut through a variety of materials including metals, woods, and plastics. The tin coating helps prevent overheating, extending the life of the drills and enhancing performance at high speeds. Tin Coated : For extra durability and heat resistance. Comprehensive Set : Includes 119 pieces and a 4-25mm step drill. Storage : Supplied in a strong metal carry case with partitions for easy organisation. Sizes : 15 x 1.0mm, 1.5mm 10 x 2.0mm, 2.5mm, 3.5mm, 4.5mm 12 x 3.0mm, 4.0mm 8 x 5.0mm, 6.0mm 3 x 7.0mm, 8.0mm 2 x 10.0mm 1 x 4-25mm HSS Step Drill Brand : PTI