Smart ring: As a professional heart health consultant, the smart ring equipped with a high-precision and high-performance heart rate sensor, accurately obtains data and monitors your heart activity 24/7. The smart ring intelligently analyzes the relationship between your activity and heart rate, while the app sends you reminders when your heart rate is too high. Specs: Size: 16/18/20mm/22mm APP software: Smart Health PPG AFE: HX3605 cceleration transducer: QMA6100P Battery capacity: 23mAh Charging case: 400mAH, can charge about 20 times Waterproof: IP68 Work time: 5-7 days for single round 90-100 days with charging case Standby time: 60 days System: Support Android 6.0, IOS 11.0 and above Material: Ceramic+stainless steel Color: Black,White