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About Drill Bits
Compare material, finish, length class, and decimal size equivalents.
Hole-Enlarging Reduced-Shank Drill Bits
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A simple way to enlarge an existing drilled hole, these bits are an economical alternative to reamers. They have four flutes that won’t catch on the inside of the hole like standard two-flute bits can, avoiding damage to the hole and your tool. The shank has a smaller diameter than the cutting tip, so you can ream large holes using tools that have standard-size chucks.
Gold Oxide—Like black oxide, this finish adds wear resistance and reduces friction for improved chip flow. Because it’s less prone to flaking off, it offers better rust protection when bits aren't in use.
Drill Bit Size | Overall Lg. | Max. Drilling Dp. | Shank Type | Each | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Gold Oxide | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
3/8" | 4.31" | 1.75" | Reduced Round | 30455A61 | 000000 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
1/2" | 4.31" | 1.75" | Reduced Round | 30455A62 | 00000 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
9/16" | 4.31" | 1.75" | Reduced Round | 30455A63 | 00000 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
5/8" | 4.31" | 1.75" | Reduced Round | 30455A64 | 00000 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
11/16" | 4.31" | 1.75" | Reduced Round | 30455A65 | 00000 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
3/4" | 4.31" | 1.75" | Reduced Round | 30455A66 | 00000 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||