Hyjoy 3PCS SAE 1/8" to 1-1/8" M35 Cobalt Step Drill Bit Set, 1/4" Shank Metal Unibit Step Drill Bits (TiAlN ), Spiral Cone Drill for Steel, Shee

【3-Piece Spiral Flute Step Drill Bit Set Widest ! 1/8" to 1-1/8" Coverage】: Most 3-piece step drill sets stop at 7/8". Our set includes 3 bits offering 29 precise hole sizes, from fine 1/8" (3.175mm) to powerful 1-1/8" (28.575mm). Set contains 3 -ground step bits providing 29 standard hole diameters: 6-Size Bit: 3/16", 1/4", 5/16", 3/8", 7/16", 1/2"; 10-Size Bit: 1/2", 9/16", 5/8", 11/16", 3/4", 13/16", 7/8", 15/16", 1", 1-1/8"; 13-Size Bit: 1/8", 5/32", 3/16", 7/32", 1/4", 9/32", 5/16", 11/32", 3/8", 13/32", 7/16", 15/32", 1/2". Handle various tasks with one set – save time and effort! 【 Build: Industrial M35 Cobalt Steel TiAlN 】: Fabricated from M35 Cobalt HSS (ISI M35/1.3243/SKH55/M35), providing wear resistance, pressure tolerance and sinter resistance – efficiently cuts through materials steel. The TiAlN (AlTiN) hardness (~3800HV), resistance ( to 800° oxidation temperature), and low friction, significantly prolonging bit life and ensuring smoother, faster . [4 Spiral Flutes: Unmatched Stability 2X Lifespan]: Eliminate the chatter! The 4-flute configuration offers outstanding rigidity and stability for enhanced and speed. Efficient chip removal reduces jams and buildup. Performs in steel applications. Lasts to 2X longer than typical step drills! [Optimized Angles Tip]: Engineered angles resist self-wear. Tip: Bits during continuous -speed . Using fluid or coolant is highly recommended for effective , maximizing bit lifespan. 【Efficient】: Step Bits feature jam-free : The dual-flute design delivers to 2X faster , 4X longer life, and 50% more holes per bit than competitors! Suitable for steel, aluminum, wood, and plastic sheet (thinner than step height). Industrial-grade reliability for professionals and DIYers.