In China, there are generally two size versions of the ring, one is the mainland version of the ring size, one is the Hong Kong version of the ring size. The continental version of the 15-yard ring has a circumference of 55mm and a diameter of 17.5mm; The Hong Kong 15-yard ring has a circumference of 57mm and a diameter of 17.3mm. Generally, the ring number 7 or 8 refers to the ring size of the United States, according to the international size comparison table, it can be seen that the American size of the Chinese version of the ring size 15 is about 7.
