<p><b>Product Size:</b></br> Size 6: The inner circumference is about 51.9mm, the inner diameter is about 16.5mm, and the error is about 1mm</br> Size 7: The inner circumference is about 54.4mm, the inner diameter is about 17.3mm, the error is about 1mm</br> Size 8: The inner circumference is about 57mm, the inner diameter is about 18.1mm, the error is about 1mm</br> Size 9: The inner circumference is about 59.5mm, the inner diameter is about 18.9mm, the error is about 1mm</br> Size 10: The inner circumference is about 62.1mm, the inner diameter is about 19.8mm, the error is about 1mm</br></p> <p><b>Jewelry maintenance:</b></br> 1. Gently, avoid collisions and friction.</br> 2. Avoid contact with high temperatures and acid, alkali solution.</br> 3. It can be easily removed when bathing or swimming.</p>