FM transmitter BC72
1. bluetooth V5.0 
2. Support dual LED Display, battery voltage real-time detection and display
3. Support QC3.0 (QC18W),PD3.0(PD18W)
4. Volume level is not adjustable, volume level defaults to maximum
5. Support Siri/Google voice assistant
6. Support stereo FM Transmitter
7. Support power off memory function 
8. Support bluetooth reconnect automatic
9. bluetooth support A2DP,AVRCP,HFP,HSP 
10. Support private answer
11. Support bluetooth stereo music DSP technology
12. One key to turn off FM Transmitter, retain charging function
13. Support input over-voltage protection, output over-current protection, output short-circuit protection and over temperature protection