Smart Watch, Virmee VT3 Fitness Tracker with Heart Rate Monitor Blood Oxygen Meter Sleep Tracking Step Counter, IP68 Waterproof Pedometer Smartwatch for Men Women, for iPhone Samsung Android PhonesAbout this itemHealth Tracking -- 24*7 tracking your heart rate, Blood Oxygen, Sleep stage(Light, Deep, Awake, REM), Stress status, to let you know your physical conditions better. Easy to check your ste..