Titanium Step Drill Bit & Countersink Set. Also includes a countersink drill bit set in sizes: 1/4", 3/8", 1/2", 5/8", 3/4". Includes 5 step bits in sizes: 3/16-1/2", 1/8-1/2", 1/4-3/4", 3/16-7/8", 1/4-1-3/8", effectively replacing 50 sizes of conventional drill bits.
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