Amazfit T-Rex Pro Smart WatchBody material: PolycarbonateStrap material: Silicone rubberStrap length: 122mm (long), 78mm (short)Strap width: 22mmWater-resistance grade: 10 ATMTouchscreen: Tempered glass + anti-fingerprint coatingDisplay: 1.3" HD AMOLED Display; Resolution 360 X 360; Always-on DisplaySensors: BioTracker 2 PPG bio-tracking optical sensor; 3-axis acceleration sensor; 3-axis gyroscope sensor; Geomagnetic sensor; Ambient light sensor; Barometric altimeterPositioning: GPS+GLONASS, GPS+BeiDou, GPS+GalileoBluetooth: Bluetooth 5.0 BLEBattery: 390 mAh lithium-ion polymer battery (typical value)Charging time: Up to 1.5 hoursCharging method: Magnetic 2-pins Pogo PinBattery life: Typical usage: up to 18 days; Heavy usage: up to 9 days; GPS continuous working time: up to 40 hoursOperating system: RTOSSupported devices: Android 5.0 or iOS 10.0 and aboveApp: Zepp App