Hand Drill Bit Set, 3 pcs. from HSS DIN 352 Metric ISO thread according to DIN 13 Tolerance class ISO 2 (6h). Material: HSS = high-performance high-speed steel. For easy to machine Steels up to 750 N / mm2. Set consisting of: Pre-, medium-, and final cutters. Measure: M 18 Pitch: 2.50 mm Shank outer square: 11.0 mm