Bluetooth 5.0 & Smart Noise Cancellation Technology: Bluetooth 5.0 chip ensures stable connection/fast transmission/wide signal range. The latest CVC8.0 noise reduction and digital signal processor (DSP) technology cancels echoes and blocks intrusive background noise such as wind, traffic or crowds, giving you crystal-clear call quality. 1. Bluetooth 5.0+EDR 2. Bluetooth transmission distance 5m 3. Support Bluetooth hands-free call function 4. Support Bluetooth A2DP stereo 5. Support answering, hanging up, rejecting, calling back and other telephone functions 6. Support echo cancellation and noise suppression (CVC) technology during calls 7. Lithium battery specification: 250mA/h 602025 8. Charging time: about 2.5 hours 9. Working hours: about 8-10 hours 10. Dual-device connection: After successfully connecting the first device, turn off Bluetooth, and then connect the second device. After the second one succeeds, turn on the first bluetooth device 11. Frequency response: 20-20khz Packaging accessories: 1. Bluetooth music receiver host 1 set 2. USB charging cable 1 piece 3. 3.5mm audio conversion cable 1 piece 4. 3.5mm metal adapter 1pc 5. English product manual 1 copy