Features 1、4 Flute Design: This step drill bit features a 4 flute design that makes cutting faster, smoother and more efficient. 2、High Hardness: This step drill has a surface hardness of 89 HRC, allowing it to cut harder materials and achieve higher cutting speeds. 3、Excellent M35 HSS And Cobalt Material: This step drill bit is made of excellent M35 HSS and cobalt material, which is strong and wear resistant, not easy to be damaged, and has a long service life. 4、Wide Application: This step drill has a wide range of applications and can be used on stainless steel, sheet metal, wood, plastic, aluminum, copper and other metal sheets. 5、Multiple Hole Punch Sizes: This step drill can punch multiple sizes of holes, such as 3/16 inch, 1/4 inch, 5/16 inch, 3/8 inch, 7/16 inch, 1/2 inch. Specification Item Type: Step Drill Bit Material: M35, Cobalt Hole Diameter: 3/16 Inch, 1/4 Inch, 5/16 Inch, 3/8 Inch, 7/16 Inch, 1/2 Inch. Shank Diameter: 1/4 Inch Package List 1 x Step Drill Bit 1 x Storage Box