IRWIN HSS Pro Titanium Drill Bits designed for drilling metal and harder alloys, as well as being able to produce increased drill speeds of 40%-60% in comparison to the standard bits. With a titanium nitride coating for higher friction resistance and longer bit life. Its 135 split point ensures perfect centring and minimises bit walk, whilst also reducing drilling pressure, giving a more accurate and clean finish. Heavy-duty web construction is designed for optimum strength and durability. 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.