1. Clear talking voice super large speaker unit loud sound and no echo; 2. Easy installation on steering wheel hands-free to answer phone calls when driving safe and convenient; 3. Large buttons for easier operation 4. Replacement & rechargeable 650mAh lithium battery; 5. Voice prompts when calls in / out Bluetooth matching on / off etc. And also with Chinese / English / Spanish multi-language; 6. Supports connecting two devices at the same time; 7. Compatible with various cell phone such as IPHONE / Blackberry and other digital devices' 8. Low power consumption design standby time about 40 days.