Hands-free calling while driving, safe and convenient. Excellent sound quality with D.S.P. solution for echo cancellation & noise suppression (CVC). Support the remote control to meet dials or pick up telephone. Broadcast music stored up by the automobile through car stereo system. Stereo Bluetooth and FM transmitter technology. Support SD/MMC card. Support MP3/WMA music format. Automatic last memory. 20 keys remote controller and steering remote controller. Rated voltage: 12V-24V. Rated current: 90mA. Limitted voltage: 9-26V. Support file format: MP3, WMA. Bluetooth voice with AD2P. Transmit distance: 10M. Bluetooth microphone effective range: 0.5 -2M. Transmit frequency: 87.5-108MHz.