Zeblaze Btalk 3 GPS 1.43 inch HD AMOLED Screen Health Fitness Smart Watch, Support Bluetooth Call Parameters 1. Bluetooth: BLE 5.2 2. Dimensions: 45.2x45.2x10.9 mm 3. Weight (without strap): 26.2 g (with wrist strap), 43 g (without wrist strap) 4. Material: durable, comfortable and removable strap 5. Minimum and maximum wrist size: 130-235mm 6. Body material: plastic bottom shell + middle frame spray 7. Waterproof level: 3 ATM 8. Screen material: AMOLED 9. Screen size: 1.43 inches 10. Resolution: 466x466 pixels 11. GPS positioning: integrated GPSBDS, assisted GPS for fast positioning 12. Health: wrist heart rate monitor, Pulse Ox blood oxygen saturation monitor 13. Battery capacity: 300 mAh lithium polymer battery 14. Standby time in power saving mode: up to 25 days 15. Training time in power saving mode: up to 14 days 16. Training time with full GPS and HR tracking enabled: up to 180 hours 17. Charging method: magnetic charging cable 18. Theoretical charging time: about 1.5 hours 19. Application: Fitbeing 20. Supported devices: Android 5.0 or iOS 10.0 and above 21. Operating temperature: 0 degrees Celsius to 55 degrees Celsius, below -20 degrees Celsius may affect battery life and performance Features 1. Activity tracking: activity record, pedometer, stand, move bar (displayed on the device after a period of inactivity; reset by walking for a few minutes), automatic goal (learns your activity level and assigns a daily step goal), calorie consumption, real-time pace and distance 2. Twenty-four-hour monitoring: wrist heart rate (abnormal heart rate alert), steps, stand, calorie consumption, real-time distance 3. Manual measurement: wrist heart rate, SpO2 (blood oxygen) level measurement, stress level, female cycle tracking, breathing training 4. Sleep quality monitoring: sleep stages (including REM), sleep schedule, sleep score and insights 5. Available running modes: GPS-based distance, time and pace, custom activity goals, real-time steps,