Four Spiral Flute Step Drill Bit Set, 5Pcs 1/8"-1-3/8" Step Bits For Metal, Hss Handle Drilling Tasks with Ease: With four sharp cutting blades, step drill bit set ensures swift, smooth drilling, effortlessly cutting through steel, aluminum, copper, and other tough materials like a hot knife through butter HHS Steel Construction: Our drill bits are made from robust high-speed steel, which offers exceptional hardness. This allows for faster cutting of harder materials while also withstanding high temperatures and cutting forces, ensuring long-lasting performance 5PCS Drill Bit Set: Our 5-piece step bit set caters to diverse drilling needs, with diameters ranging from 3/16" to 1/2" (6 steps), 1/4" to 3/4" (9 steps), 3/16" to 7/8" (12 steps), 1/8" to 1/2" (13 steps), and 3/16" to 1-3/8" (19 steps) ? Quick Release Tapered Edge Design: The 1/4" hex shank and quick-release slot ensure secure connections and easy changes. The four-spiral flute design effectively evacuates chips from the hole, reducing the likelihood of clogging and improving drilling efficiency Easy Organization Identification: Our step drill bits for metal come with a handy storage case, ensuring effortless organization and portability for all your drilling tasks. Clear size markings on each bit allow for quick identification