Dual USB Car Charger: This Bluetooth car adapter has 2 USB charging ports to charge most USB Devices((5V-3.1A and 5V-1A). Input 12V/24V. This feature allows you to charge your mobile devices while driving. This is especially useful for long drives or when you rely heavily on your mobile device for navigation or music streaming. Car Battery Voltage and Portability: The car aux Bluetooth adapter shows 3 seconds of voltage when plugged into the outlet port. Always keep the battery state health. Then it turns to automatic play mode. The Bluetooth transmitter comes with a compact and portable design, allowing users to easily move the transmitter between different vehicles or even use it in rental cars or friend's vehicles. Handsfree Function: The car's Bluetooth adapter with built-in microphone and call-handling features, switches to hands-free mode automatically from music playing status when receiving calls. Answer/Reject/Hand up/Recall all in One key. This enables hands-free calling while driving. The FM transmitter broadcasts the call audio through the car's speakers, ensuring clear communication without the need to hold the mobile device. More Compatibility: This Bluetooth cigarette lighter adapter can transfer calling/MP3 Music/Cellphone voices to the car radio. Compatible with iPad,iPhone, Samsung Galaxy, Google, LG, HTC, and Bluetooth devices. By pairing your device with the transmitter, you can stream music, podcasts, audiobooks, voice navigation, or any other audio content from your device to the car's radio. Music Streaming Adapter & Player: Wireless Bluetooth FM transmitter adapter support Bluetooth /USB disk/TF card/ MP3/WMA player. With anti-interference performance and CVC technology.Listening to music while charging. Automatically connect memorized paired when powered on. Support WMA MP3 WAV APE FLAC music formats.