About Product 1. Main Chip: Pixart 28602. Bluetooth: 5.13. Sensor chip: QMA6100P4. Heart rate sensor: HX36055. Battery Capacity: 18m. Ah 6. Working time:About 5-7days 7. Charging time: About 0.5H8. Waterproof: IP68 waterproof 9. Size 8: Dia 18.1mm; Perimeter 56.9mm 10. Charging method: Magnetic charging 11. Compatible system: Android 6.0 or above, iOS11.0 or above 12. APP: ECTRIPacking list:Smart ring x 1. Charging cable x 1. User manual x 1. Original retail box x 1