Small ruler-like tools with graduated holes, often indicating both metric and imperial sizes, designed to identify the size of knitting needles and crochet hooks. These tools are especially useful for identifying the size of double-pointed needles, interchangeable needles, vintage needles, or other types of needles that are not labled for size. Unmarked needles are inserted into the gauge's various holes until the most similarly sized gauge hole is found and the needle's measurements are determined.
