Size: 5 * 2 * 0.7CM<br>Color: Silver<br>Cable length: 80CM<br>Max sound output: 127 ± 4 db<br>Max adding: 52 db ± 5 db<br>Harmonic distortion: ≤5%<br>Low Frequency: 580Hz~2.8KHz<br>Middle Frequency: For 700Hz~ to 4.8kHz<br>High Frequency: 780Hz~7.8KHz<br>Wide operating frequency: 910Hz~10.5KHz<br>Input Noise: ≤30dB<br>Battery: Lithium Battery<br>Working voltage DC5V ± 0.5V<br>Operating Current: ≤2.5mA<br><br /><img src="http://img6.eachbuyer.com/x9/p100/bc912_1.jpg" />                                                        <img src="http://img6.eachbuyer.com/x9/p100/bc912_2.jpg" />                                                        <img src="http://img6.eachbuyer.com/x9/p100/bc912_3.jpg" />                                                        <img src="http://img6.eachbuyer.com/x9/p100/bc912_4.jpg" />                                                        <img src="http://img6.eachbuyer.com/x9/p100/bc912_5.jpg" />                                                        <img src="http://img6.eachbuyer.com/x9/p100/bc912_6.jpg" />