Jewelers, watchmakers, and gemologists use gauges and measuring tools to document, communicate sizes, plan a design, and repair. Widely used in so many trades, these gauges are precision set and ideal for measuring small parts and designs. Many of the gauges and calipers can measure the inside diameter as well as the outside diameter using caliper arms that will reach into small areas. Because of their versatility, these gauges are a great addition to any workbench: they can measure gemstones, measure watch bands, measure watch hands, ring sizes, millimeter size, and so much more.