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Stone Tools ST-333 1/2-Inch, 1/18-Inch and 1-3/8-Inch Sizes Titanium Step Drill Bit
Cuts 10 different hole sizes from 1/4-Inch to 1-3/8-Inch
Lasts 6 times longer and penetrates 75-Percent faster than high speed steel step drill bits
Ideal for tough cutting jobs and industrial production
Runs cooler, requires 25-Percent less force
Designed with a double flute for smooth fast penetration