Professional swimming SWOLF, based on HRV health function, Afib, blood oxygen (optional) Clock, date display Data storage/OTA upgrade/Breath training Heart rate monitoring/Sleep monitoring/Step monitoringColorie  monitoring/Standing monitoring/Distance monitoring Arrhythmia monitoring/Blood oxygen function/Pressure value functionMaterial: Zinc + SiliconeScreen size: 1.3 inchesBattery: 220mAhChip: NRF52840Resolution: 240x240Waterproof: 5atm