Key Features:1.3inch high-definition screen with 2.5D tempered glass lens, IPS true color screenIP67 waterproof and Multiple sports professional modePrecision dual optical heart rate monitor with double optical heart rate monitoringCompatible with Android, iOS system, support Music controlManufacturer SpecificationsGeneral:CPU: NRF52832 QFAADisplay Size: 1.3InchDisplay Resolution: IPS 240x240Heart rate sensor: Green Light Static Heart Rate SensorBluetooth 4.0Functions: Blood Pressure, Heart Rate, Pedometer, Sleep Monitor, Alarm Clock, TimeBattery Size: 220mAhBattery Built-inApp Name: Da FitCompatible OS: Android 4.4 / iOS 9.0 and above systemWeatherproof IP67Companion Function (with smartphone):Incoming call and Message reminderMusic ControlRemote cameraDimensions:Main Product Weight: 51gWeight/dimension is for the main item of this boxed product, to help you compare product sizes before buying: please do not base your shipping calculations on this price - shipping prices depend on you