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descriptions: 2. chip: nrf52832 3. bluetooth: bt4.0 4. compatible system: android 4.4 and above, ios 9.0 or above 5. waterproof rating: ip67 6. screen: 1.3 inch ips color resolution: 240*240 7. touch: single touch 8. battery: 180 mah 9. charging: magnetic charging 10. charging time: about 1.5h 11. standby: 25 days or so working time: 7 days or so 12. bracelet material: pc case + plastic case 13. product size: about 48.9*34.5*11.7mm/1.92*1.35*0.46in 14. net weight of the product: about 25.7g