All the rings are American. It's the size of a ring. Please view the international size chart photos. The United States ring size 5 = 16 mm diameter size 6 = the United States is about 16.5 mm diameter size 7 = America is about 17.5 mm diameter size 8 = 18 mm diameter size 9 = the United States about 19 mm diameter size 10 = America about 20 mm diameter size 11 = 20.5 mm diameter size 12 = 21.5 mm diameter size 13 us size 14 = = about 22.5 mm diameter 23.5 mm diameter species: the ring material: stainless steel (male) black gold filled (female) style: wedding ring color: black and blue Mainstone: sapphire ring size: # 5 # 6 # 7 #, 8 # 9 # 10 # 11 # # # 11 12 13 package contents: 1 * ring (not a pair of rings) suitable for occasions: wedding/party/engagement/advice/leisure/gift/anniversary