Features: Aluminum alloy body, thick, feel is also very good. Mini HIFI audio power amplifier. Internal 5.0 Bluetooth version module. Low distortion supplies a clearer, stronger and more powerful sound. Two main channel output, left and right channel outputs are interfaces for speakers. Large knobs are designed with blue led lights to make the products more beautiful. Specification: Input voltage: DC12V Current requirement: above 2A Product power port: 2.1X5.5mm Frequency Response: 20Hz - 20KHz Out Power: 2 x 20W Impedance: 4 - 8Ω Signal To Noise Ratio: 85dB Audio Sensitivity: 0.25mv-50mv Number of Channels: 2 Material: aluminum alloy Color: Black Package Contents: 1 Amplifier Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.