Features:High-quality materials: Made of high-quality materials, they are wear-resistant and sturdy, not easy to break, and can be used for a long time.Mobile APPscontrol: The mobile APPs can view monitoring data in real time. The APPsneeds to be connected to the ringsthrough Bluetooth-compatibleon the mobile phone. Keep the Bluetooth-compatibleturned on. The Bluetooth-compatiblewill automatically connect when the APPsis started. When not connected to a mobile phone, the rings can also independently monitors the body, record blood oxygen and heart rate status, and update the data in the APPsafter being connected.IP68 waterproof level: The Bluetooth-compatible ringsadopts a fully enclosed structure and IP68 waterproof technology, which can easily cope with daily waterproofing. It can be worn for swimming, hand washing, raining, etc. to meet your various waterproof needs.Magnetic fast charging: This Bluetooth-compatible ringsuses magnetic charging, which has fast charging speed, long battery life, and APPs can check the real-time battery level.Multifunctional: The Bluetooth-compatible smart rings can measure steps, distance, calorie calculation, heart rate, blood oxygen saturation, blood pressure, sleep tracking, and is multifunctional.Notice:1.Actual color may be slightly different from the image due to different light effect2.Please allow 1-3cm deviation due to manual measurementDescription:Material: Stainless steelSize: Bracelet size inner diameter (mm):Size 8: 18.1mm, Size 9: 18.9, Size 10: 19.8mm, Size 11: 20.6mmBattery Capacity17mAhCharging Method: Magnetic chargingBluetooth-compatible version: 5.0Waterproof Level: IP68Note: 1. Please clean the charging interface regularly to avoid being unable to charge due to dirt.2. Please take off the ringsand clean it after bathing to avoid skin damage caused by toiletries residue inside the rings.