The hole sizes and decimal equivalents are permanently etched on face so they won't wear off with repeated use. Number size drills 61 to 80. Fractional size drills 1/16 to 1/2 in x 64 ths. Metric range from 0.062 to 0.500 mm. This gage has been crafted to meet government specifications.
Drill gage is a useful guide for identifying drill bit sizes, extremely helpful when working with older, unmarked drill bits, as well as with bits that are too small to fit diameter markings. Measures bits from 1/16 to 1/2 in x 64ths metric range from 0.062 to 0.500 mm, made from heavy-duty stainless steel with black etched graduations.