Comprehensive Sizes - Includes Half Sizes Our ring measuring tool sizer has 27 sizes in total - Each ring is laser engraved with USA Sizes 1-13 including 1/2 half size increments. Our range measures child fingers to largest fingers. tool sizing Detachable Hook Our sizers are fully detachable. Detach the sizes you need, enjoy the convenience of bringing only what you need. Stainless Steel material is used for all our ring gauges sizing tools. The color does not oxidize and material is durable and sturdy enough to last a lifetime.