• For making holes in thin sheet metals • Titanium-nitride (TIN) coated step drill with a surface hardness that makes the tool last 4 to 5 times longer than ordinary step drill bits • Same surface reduces friction, resulting in a tool that runs cooler and effective, self-lubricates while running dry • Self-centering point • Drills holes from 4 mm to 22 mm in 2 mm increments • Shank 3/8" (10 mm)