Professional tool for commercial or occasional use. Fully precision ground HSS for strength and durability Long lasting working capacity. 135 degree split point design Metric size drills Made from 4241 Steel. This is the very best grade of HSS steel. This set of twist drill pieces have been precision ground and heat treated for extra strength and durability. These have a long lasting working capacity and use a 135õ Split Point Design. Comes in metal tin for easy storage and transportation. The tin comes with numbered holes so that you can find the drill easily and efficiently. Set Includes; Sizes: 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm, 5mm, 5.5mm, 6mm, 6.5mm, 7mm, 7.5mm, 8mm, 8.5mm, 9mm, 9.5mm, 10mm, 10.5mm, 11mm, 11.5mm, 12mm, 12.5mm & 13mm.