●【Precious materail】14K real gold, the gold earring backs stamp AU585 / 585. Good for everybody, best choice for those who have sensitive ears. ●【Wide applicattions】Hole diameter is 0.8mm(approx 0.036inch) . It can fit earring post hole diameter under 0.8mm, widely applicable for most diamond stud earrings/ pearl post earrings. ●【Convenient to use】Simply sliding the earring post into the earring back, you can lock the earring comfortably and securely. ●【Quality Assurance】We Provide a 30-Day Refund Service. We are pretty confident that the earring back will become the number one choice every time you go out! ●【Lulau & LUCKMORA】We have two brands operating in the jewelry business at the same time.