1. Bluetooth version: 4.12. Noise reduction version: CVC8.03. Working distance: open (unblocked) 25 meters4. Battery capacity: 45mAh5. Continuous talk time: about 2.5 hours6. Continuous music listening time: about 3.5 hours7. Headphone material: PC8. Weight: 3.5g9. Function: answer the call, hang up the phone, listen to music, call reminder, mobile phone battery display

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