Design 2.5d Curved Surface Borderless Design Size 42.8 X 35.6 X 9.8mm Weight 25g (without Strap) Body Aluminum Alloy Bottom Shell Plastic Matte Bottom Case Buttons 1 Waterproof Grade 5 Atm (50 Meters) Screen Size 1.65 Inches Material Amoled Touchscreen Tempered Glass+ Anti-fingerprint Vacuum Coating Resolution 348x442 Ppi 341 Battery Capacity 246mah (typical Value) Charging Method Magnetic Charging Stand Charging Time About 2 Hours Typical Use Battery Life 14 Days Basic Use Battery Life 24 Days Heavy Use Battery Life 7 Days Health Huami Self-developed Biotracker™ 2 Ppg (support Blood-oxygen) Biological Data Sensor Movement Acceleration Sensor, Gyroscope Sensor, Geomagnetic Sensor, Ambient Light Sensor, Air Pressure Sensor, Temperature Sensor Connection Bluetooth 5.0 /ble Positioning Gps + Glonass Strap Material Silicone Width 20mm Clasp Classic Pin Buckle Installation System Quickelease Microphone Support Linear Motor Support Temperature Sensor Support Core Functions Comprehensive Health Care, Intelligent Voice Assistant, Professional Sports Modes, Temperature Monitoring Supported Devices Android 5.0 Or Ios 10.0 And Above Application Zepp App