CORTOOL Step Bit 3/16 to 1-1/4 Inch HSS Co M35 Cobalt Step Drill Bit for Stainless Steel and Hard Metal (18 Steps)

CORTOOL Premium M35 5% Cobalt Steel, 66-69 HRC (Rockwell Hardness Scale), Usually Give the Best Heat, Wear and Chip Resistance and Long Tool Life. Grinding the Cutting Edge Three Times, with the High HRC and Heat Resistance of the Material, Designed for Cutting through Stainless steel, Iron plate, Aluminum, Ducts, Wood, PVC and Plastic. This Cobalt Step Drill Bit is Typically Capable of Running Two to Three Times Faster. Despite the Higher Price, the Cost Per Hole When Using Cobalt Drill Bit Will be the Lowest, Since It Can Produce So Many More Holes. 18 Steps One bit for all: 3/16" 1/4" 5/16" 3/8" 7/16" 1/2" 9/16" 5/8" 11/16" 3/4" 13/16" 7/"8 15/16" 1” 1-1/16" 1-1/8" 1-3/16" 1-1/4" Jam-Free Performance: Spiral dual-flute design and three-sided shank design is optimized for cordless drills in high speed provides greater speed and control while minimizing steel scurf flying around, to lengthen service life, please do not set drilling speed at its maximum to avoid damage to the cutting edge.