Acten Steering Wheel Auto Hands Free Bluetooth Speakerphone Car Kit FM Transmitter W5 Features: Bluetooth 2.0support to play Hi-Fi stereo music Full DuplexDSP TechnologyEcho cancellation and noise reduction Built-in FM Transmitter and support full frequency range 88.1-107.9MHz Built-in 800mAh Li-ion batteryover 7 days standby time Compatible with all kinds of cars Caller ID display and shows callers name Support voice report TTS reporting Support Micro-SD cardup to 32GB, and MP3 file format Can store 600 group telephone numbers Specifications: Bluetooth specification: 2.0V Support profiles: HSP/HFP 1.5, a2DP, OPP Battery: 800mAh Charging input voltage: DC5V, 0.5A Charging time: within 4 hours Talking time: Up to 15 hours Standby time: Up to 7 days Operating temperature: -2050 Storage temperature-3060