Package includes: You will receive 1pcs ring sizer, 1pcs black American standard ring sizer finger gauge (US standard) and 1pcs white UK standard ring sizer finger gauge (UK standard). Standard size: marked both with US size (0-13); and UK Size (A-Z). For example: "1 C" (1 means US size "1", while C means UK size "C"). US size has half sizes, represented by "-", for example, -1 is 1.5. Perimeters and diameters are also marked on them for people from different countries to use. Material: The ring size is made of sturdy black plastic, lightweight, easy to carry and store. And comfortable to wear. Can be separated: The calibrators are delivered on a cable which can be separated if necessary. Simply unscrew the cable and you can remove the calibrators. Application: Ring measuring tools are helpful in choosing a suitable ring. With them you can immediately get a correct ring size at home, no need to go to the jewelry store. Perfect for measuring wedding rings. Essential accessories for jewelry stores, ring counters, etc.