uxcell Step Drill Bits Set HSS 312mm 412mm 420mm Titanium Coated Straight Flutes Hex Shank for Metal Wood Plastic

Features: Laser marking makes the size more clear; High speed steel for longer service life; Used on electric drills and drill presses; Double cutting blades design enables a faster and smoother cutting; Hexagonal shank prevents slip in electric drills and presses’ chuck; X-type openings design to facilitate the removal of cutting waste when drilling; The sharpness and titanium coating ensure easily cut through most metal, aluminum, plastic, wood and other materials with ease; Specifications: Product Name: Step Drill Bits Color: Golden Weight: 85g Surface Treatment: Titanium Coated Material: High Speed Steel Shank Diameter: 6mm / 0.24 inch 3-12mm: Step Quantity: 10 Total Length: 80mm / 3 inches Cutting Diameters: 3mm/0.12", 4mm/0.16", 5mm/0.2", 6mm/0.24", 7mm/0.28", 8mm/0.3", 9mm/0.35", 10mm/0.4", 11mm/0.43",12mm/0.47" 4-12mm: Step Quantity: 5 Total Length: 70mm / 2.7 inches Cutting Diameters: 4mm/0.16”, 6mm/0.24”, 8mm/0.3”, 10mm/0.4”, 12mm/0.47” 4-20mm: Step Quantity: 9 Total Length: 72mm / 2.8 inches Cutting Diameters: 4mm/0.16", 6mm/0.24", 8mm/0.3", 10mm/0.4",12mm/0.47", 14mm/0.55", 16mm/0.6", 18mm/0.7", 20mm/0.8" Package Contents: 3 x Step Drill Bits Maintenance Tip: 1.Not compatible with hammer drill. 2.It is recommended to oil the bit before every use. 3.Please drill a smaller hole to make drilling smoother. 4.Please do not set drilling speed too high to avoid damages to cutting edge. 5.The metal sheet on which you want to drill should not exceed 0.38” in thickness. 6.Check the concentricity of the spindle and spring chuck and the clamping force of spring chuck, for it may cause the drill bit broken and make drill hole too large.