["brand new and high quality\nFeatures:\nUnique ladder structure, it can open multiple aperture.\nIt can deburr, chamfer and open hole, but ordinary twist drill can'for t.\nLittle rock, it can carve out a nice aperture without firstly using a center punch.\nWater to make ti cool while working, it can effectively extend the service life. \nDeburring, chamfering, elliptical hole enlargement, twist drills, drills, table drills.\nWidely used to cut holes in a variety of material like steel, wood, thin iron, aluminum alloy, insulation boards, PVC sheet,ect.\nRecommended drilling speed 250--400 rpm.\nSuit for use in hardness under 25° artifacts,The plate thickness under 5mm.\nStep Drill Bit only, other accessories demo in the picture is not included.\n\nSpecifications:\nMaterial: HSS\nSize: app.app.10.6x1cm/4.17x0.39in\nStyle: 4-52mm（4,8,12,16,20,24,28,32,36,40,44,48,52mm）\nColor: Golden\nQuantity: 1 Pc\n\nNote:\nNo retail package.\nPlease allow 0-1cm error due to manual measurement. pls make sure you do not mind before you bid.\nDue to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you!\n\nPackage Includes:\n1 x Step Drill Bit"]