Shown are 12mm stud earrings. This is the most popular size for both adults and kids! Earring Sizes (diameter of earring face): • Regular 12mm = .47in • Medium 10mm = .39in The “setting” refers to the metal part of the earring. If a specific setting color is not requested, we will send as shown in the default photo. Settings are Nickel, lead, and cadmium-free. Posts are centered on the back.