Power effective: 5W x 2 P.M.P.O.: 650 watts Size: 106x107x109 mm Frequency response: 90Hz-20KHz Speaker specifications: 2.5inch full range (66mm) Impedance: 3 ohm Supply: 5V (USB) Sensitivity: 600±100 mV Distortion: 1% 1W 1KHz Signal to noise ratio:70dB