Since the traffic law have strictly controlled  the calling when driving .Bluetooth headset sales very well,but the problem will be coming 

1，The trouble is charge the Bluetooth headset in the car,

2, Bluetooth headset sound quality is not good,No noise reduction.

3, Security issues,Poor quality Bluetooth headset too,Into the carry-on battery charging will be short-circuit happenning

4, The purchase of an ordinary car charger Bluetooth,There is no USB charging port to power other electronic devices,

5, there is no intelligent output voltage of the car charger, or charging slow, or damage the charging device.

Therefore, when buying a carcharger with Bluetooth the quality is very important