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Stone Tools ST-329 3/16-Inch to 7/8-Inch in 1/16ths, 12 Steps Titanium Step Drill Bit

Cuts 12 different hole sizes from 3/16-Inch to 7/8-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