FM transmitter BC71
1. bluetooth V5.0
2. Support dual digital tube display, real time detection and display of battery voltage
3. Support orange USB interface(QC18W),Type-C interface(PD20W) 
4. Support Colorful atmosphere LED
5. Support the voice assistant
6. Support TF card,WAV/PLAC
7. Support music, volume, point power off memory function
8. Support bluetooth automatic loopback
9. Support A2DP, AVRCP, HFP, HSP
10. Support private answer switch
11. Support key on / off, retain charging function
12. Supports input over-voltage protection, output over-current protection, output short-circuit protection and over temperature protection