Features DRILLING RANGE: This step drill has drilling diameter of 3/16in to 1‑3/8in, for different hole processing to improve efficiency. 3/8IN HEX SHANK: With a standard 3/8in hex shank, suitable for installation on the corresponding electric drill, not easy to loosen. HIGH SPEED STEEL: Made of excellent M2 high speed steel material, with high hardness and wear resistance, not easy to deform. STRAIGHT FLUTE DESIGN: The step drill bit is side straight flute chip removal design, which is convenient and efficient to operate. APPLICABLE MATERIALS: Suitable for drilling 0.2in thin metal plates, wood boards, PVC and other materials, with strong practicability. Specification: Item Type: Hex Shank Step Drill Material: M2 High Speed Steel Surface: Nitriding Treatment Tool Diameter(in): 3/16, 9/32, 3/8, 7/16, 17/32, 5/8, 11/16, 25/32, 7/8, 29/32, 1, 1-1/16, 1-1/8, 1-5/32, 1-7/32, 1-9/32, 1-5/16, 1-3/8 Working Length: Approx. 58mm / 2.3in Total Length: Approx. 88mm / 3.5in Package List:1 x Step Drill Note:Pay attention to safety protection when using. Package List 1 x Step Drill