Specifications: 1,Max sound out put:130 /- 5dB 2,Sound gain:>= 50dB 3,Total harmonic wave distortion:<= 5% 4,Frequency range:300-4000MHz 5,Input Noise:<=30dB 6,Voltage:d.c.1.5V 7,Current:<=4mA Function: When you watch movie, enjoy the drama, attend meeting, or have classes, the product can help you to hear the sound clearly and loudly
