Hymnorq Jobber Twist Drill Bits 29pc Set, Fractionsh Inch Size 1/16 to 1/2 by 64ths in Premium Index Case, M35 Cobalt Steel, 135 Degree Split Point, for Stainless Steel Iron and Other Metals

COBALT STEEL - Manufactured from M35 cobalt steel, with molybdenum and cobalt added to create a hardened heat-resistant alloy, measuring Rockwell hardness up to 67, for much faster cutting and extra longer life span, with up to twelve times compared with an average HSS drill bit.
NO CENTER PUNCH NEEDED - The 135° Quick-Cut points are self-centering and penetrate quickly with less pressure. Will not "walk" or "wander". Straight shank allows for firmly holding and accurate centering, fit for standard drill chucks and regular round collet chucks. Must be used and operated at proper RPMs for maximum efficiency.
29PC FRACTIONAL INCH BITS - The set includes 29pcs of M35 cobalt steel twist bits from 1/16" to 1/2" in 1/64" increments: 1/16", 3/32", 5/64", 7/64", 1/8", 9/64", 5/32", 11/64", 3/16", 13/64", 7/32", 15/64", 1/4", 17/64", 9/32", 19/64", 5/16", 21/64", 11/32", 23/64", 3/8", 25/64", 13/32", 27/64", 7/16", 29/64", 15/32", 31/64", 1/2". Well packaged in a tough index ABS plastic case.
FOR METALWORKING - Particularly successful in cutting through hard metals such as stainless steel and cast iron(not for heat treated steel, hardened steel and high carbon steel), although they can be used for softer materials, too.
DOWNLOADABLE USER GUIDE - We've summed up some tips of drilling metals, including a RPM chart for several common metals, based on our reviews and some articles on the internet. In most cases, our customers would get a much better result with these tips. Welcome to download.