Portable back-hang design, convenient for sports Suitable for mobile phones, PC, and iPod Handsfree speaking by pairing with mobile phone Enjoy music of iPod with adaptive dongle Can receive and reject incoming calls while automatically stop music Volume adjustment Bluetooth version: 1.2/V2.0, wireless transmitter standard of class II Chipset: CS2 Frequency coverage: 2.402~2.480GHz ISM band Sensitivity: -80dbm Transmit speed: 57~723Kbps Stereo compression ratio: 44.1/48kHz Channel: 79 channels of 1MHz, B/W Contact terms: Point-to-Point Battery: Li-ion. 3.7V/150mA Charge power : PC USB, 5V Charging time: 1-2 hours