Screen Size: 2.5 inches Endurance: 30 hours Charging Time: 3.5 hours Standby Time: more than half a year Positioning System: 4-Satellite positioning system positioning Waterproof Rating: IPX6 Extensible Peripherals: heart band, pedal, speedometer, power meter Training Function: ring recording, heart rate warning, power warning Automatic Backlight: Yes Automatic Calibration: Yes Product Size: 7555 18mm Storage Capacity: 8M Data Types That Can Be Displayed 9 categories with 37 items