Description3pcs M7 HSS Step Drill Bit Set 3 16 1 2 1 4 3 4 3 16 7 8 Inch Specifications Material HSS High Speed SteelShank Size Tri Flat ShankFlute Dual Flute SizeDrilling Range Φ inch Step SizesHeight mm Flute Length mm Height of Shank mm Shank Diameter Φ inch 3 16 1 2 3 16 1 4 5 16 3 8 7 16 1 2660352561 4 3 4 1 4 5 16 3 8 7 16 1 2 9 16 5 8 11 16 3 4973489 5 3 16 7 8 3 16 1 4 5 16 3 8 7 16 1 2 9 16 5 8 11 16 3 4 13 16 7 81278539 5Quantity 3pcs Features Hi Molybdenum M7 HSS Steel135° Split Point Prevents Walking Dual Flute Design Drills 17 FasterAutomatically Deburrs for A Clean and HoleTri Flat Shank Prevents Spinning in the ChuckNo need for a pilot hole can automatically deburr holes as you drill Drill bit is proud to release the newest technology in step drill bits These bits are made from Molybdenum which has a melting point of 4 753° degrees Fahrenheit These bits will drill through the toughest steel like truck frames stainless steel farm implements spring steel grade 8 bolts and more Package Included 1x set 3pcs HSS Step Drill Bits More Details