The IRWINreg; HSS Pro Drill Bits are manufactured from high-quality HSS steel. They have precision ground cutting edges for fast drilling and perfect finishing, a ground flute for maximum accuracy and fast chip removal, and a universal 118ordm; point shape for drilling a wide selection of materials. Manufactured to DIN 338 standards. This 15 Piece Set contains the following sizes: 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 8, 9, 10mm.