STEP DRILL BIT SHEET METAL PUNCH SETProduct Features3-piece step drill bit set made of high-speed steel.Double flute system for crack-free cutting.Small Drill Bit: 4, 6, 8, 10, 12 mmMedium Drill Bit: 4, 6, 8, 10, 12, 14, 16, 18, 20 mmLarge Drill Bit: 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32 mmTin coating is 6 times more durable than regular HSS bits.Package Includes1 piece of step drill bit sheet metal punch set