The OX Pro 19 Piece Multi Material Drill Bit Set is made from high speed steel fully ground to ensure precision cut and excellent abrasion resistance. Fully ground manufacturing process for increased diameter accuracy. 135 degree self-centering tip for optimal drilling efficiency & heat treated for increased durability & longer life. Suitable for drilling various materials such as wood, soft sheet metal and plastic. Set includes: 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 & 10mm.