TRENDnet TVP-SP2 VoIP USB Speakerphone (for Skype) Standard: USB 1.1 Interface: 1 x USB Type B (Female) port; 1 x 3.5mm Stereo Jack (headset); 1 x 3.5mm Microphone Jack (microphone); 1 x 5V DC in Solution: 8 Bits DSP Voice processing ; Echo-cancellation: up to 45dB ; Audio output frequency range: 44.1KHz Built-in Microphone: Sensitivity: -40 ?2dB ; Directivity: Omni Directional ; Response Frequency: 50Hz ~ 16KHz Built-in Speaker: 41 x 71mm ; Response Frequency: 100Hz~20KHz ; Output Impedance: 1W/8Ohm