About This HSS step drill with Titanium Coating – High-speed steel material ensures a longer service life.This unibit step drill bit features advanced heat/corrosion/rust resistant coating, specially engineered for demanding metal drilling applications. Multi-Material Performance – This step drill bit set effortlessly drills through steel sheets, aluminum, wood, and plastic with clean holes. The step bits are perfect for DIY home projects and professional building/engineering applications. Two Straight Flutes stepped drill bit - The dual-flute design ensures faster chip removal and cleaner holes. This step drill bits for metal provides smoother cutting while efficiently evacuating chips for peak drilling performance. Tri-Flatted Shank Step Bit Set - These professional step drill bits feature 3 precision-flatted shanks for maximum grip, eliminating slippage under high torque. The enhanced design ensures secure clamping in pistol drills. Set Includes - This metal step drill bit includes 3 common sizes for versatility, drills 28 sizes (3/16" to 1-3/8") —laser-etched markings on the unibit allow instant size identification for precision metalworking. Overview Material : High Speed Steel (HSS) Cutting Diameter : 0.5 Inches Finish Type : Titanium Shank Type : 3-Flat Cutting Angle String : 135 Degrees