Function: 1. Support hands-free calling, built-in microphone, convenience, and safety for answering the phone. 2. Noise cancellation by CVC. wind noise suppression, Ful duplex technology. Support A2DP, Play mobile music in high quality once connected by wireless. 3. Auto pairing once turns it on. 4. Support MP3 or WMA or FLAC from TF card. 5. C4 Pro will come with a car charger, output 5V-3.4A, and can charge the device in the car. Specifications: Name: Name: Car FM Transmitter Model: C4 Pro Input Voltage:12V-24V Output Parameters: 5V 3.4A U disk: Support U disk playback TF card: Support TF card music playback Size: 7.6cmx5.2cmx4cm BT: BT version: V5.0andEDR Frequency: 20h-20KHZ Voltage: 5Vand1-0.5 Frequency: 2.402-2.480 GHz Effective distance: 5m RF output: 4 dBm FM: FM:87.5MHZ-108.0MHz Emission power: 87 dBuv or 107 dBuv Effective distance: 5m Package includes: 1 x Car handsfree FM transmitter 1x Remote Control 1 x Packing box or 1 x Car handsfree FM transmitter 1 x Packing box Note: 1. Due to manual measurement, please allow 1-3 cm error. Make sure you don't mind before bidding. 2. Due to the difference of different monitors, the picture may not reflect the actual color of the product. Thanks. Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.