Specifications Hign-concerned Chemical:None Waterproof Grade:3ATM Model Number:Smart Ring Display screen:Yes NFC Support:No Activity Tracked:Activity Tracker,Steps Tracker,Distance Tracker,Calorie Tracker Metrics measured:Heart Rate Monitor,Sleep Monitor,Blood Oxygen Monitor Item Weight:2.5g Case Material:STEEL Certification:ce,FCC Brand Name:Ola Esporte Battery Capacity(mAh):16mAh Product Parameters: Name:Smart Ring Color: Black,Silver,Gold Size: 8.9.10.11.12.13 Battery capacity:16mah Theory Standby time:16-20 days Normal using time:3-4 days Charing time:2H G Sensor:SC7A20 Heart Rate Sensor:Tianyi 3918 Waterproof Level:5ATM class waterproof, diving or snorkeling can be worn to support more than 50 meters depth waterproof Charging Requirement:Charging 1A or less Compatible SystemAndroid 9.0 and above; Apple IOS 10.0 and above Size: 8#(18.2mm) 9#(19mm) 10#(19.9mm) 11#(20.7mm) 12#(21.5mm) 13#(22.2mm Major function: 1.Multisports: Multiple movement modes. 2.Steps:Double-touch and the green step light will light upand display the actual number of steps. 3.Heart rate:Touch three times and the red heart rate lightwill light up and the last test data will be displayed. Afterstaying on the interface for two seconds, it will enter the heartrate test state and the three middle bars will rotate. After thetest, the test results will be displayed. 4.Sleep:Touch five times to display the word SLEEP, and after0.6 seconds, the sleep duration of last night will be displayed. 5.Blood oxygen:Touch four times and the red heart rate lightwill light up and the words SOP2 will be displayed. After 0.6seconds, the blood oxygen test state will be switched and thethree middle bars will rotate. After the test, the test result willbe displayed. 6.Battery level: Touch six times to display the current batterylevel, the same as when charging. 7.Time: Touch to display the current synchronization time. 8.Others: Hand gestures brush tiktok,Wave your hand to take a picture immediately,Wechat&Apple. Notes: 1. After receiving the ring, please charge it first, because after a long time of logistics, the watch will be low on power. 2.The data of the health test function is for reference only, and the specific health data should be based on medical data. 3.The quick charger is not suitable for this productdon't charge with a high-power charger. 4.Before using, pleases can the QR code on the manual to download the APP and use the APP to connect with the ring.