Support mobile phone navigation voice prompts, support activation of mobile phone voice assistants Bluetooth answer, hang up, reject, redial and other functions Bluetooth standard: V5.0+ Bluetooth frequency: ISM2.4GHz-2.48GHz Bluetooth working range: 0-10M Material: plastic Built-in rechargeable battery: 3.7V 500mAh Charging time: 2-4 hours color: black Working time: up to 20 hours Standby time: up to 100 hours Package Contents: 1 x Bluetooth receiver Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.