VEVOR Step Drill Bit, 4.76 to 34.93 mm, 9.53 mm Triangular Shank, TiAlN Coating Cobalt High Speed Steel, Four Spiral Flute Step Bit for Metal, Stainless Steel, Aluminum, Wood, Plastic, FiberglassProduct Features Multi Size Versatility This step drill bit includes nineteen precise sizes from 3 16 to 1 3 8 inch to handle diverse drilling needs. Minimal bit changes help maintain an efficient workflow across projects Long Lasting Sharpness The step bit is made of cobalt high speed steel with an AlTiN coating to withstand wear and stay sharp. It is ideal for stainless steel, metal sheets, and other tough materials Optimized Cutting Angle Our step