... radio 3.new design,custom logo printing new usb speaker,good quality speaker Mini speaker(XKD5)(TF/USB/FM) This mini audio box ... . You can enjoy sweet stereo sound product from the aluminum speaker. Several power supply manners including battery, computer USB, adaptor DC ... 3dB) Signal and Noise Ratio of Power amplifier: ≥80dB Loud speaker: 1.77inch(external diameter 45mm) magnetic resistant 4 Ohms Line ...