The mic preamplifier supports common condenser and dynamic microphones. There are three output ports,Maximum amplification gain is 60dB. The adjustment range of treble, mid-range and is 15dB. With a ow-cut switch, Signal attenuation below 80HZ improves speech intelligibility and reduces microphone pops. With an overload indicator light, The indicator light light up when the microphone is too loud, and the gain knob can be adjusted to the moderate position during use. It should be adjusted to a position where the indicator light does not light up or blink occasionally. Powered by DC5V-12V. A power bank or a mobile phone charger can be used. Please use a high-quality charger, because poor power supply produce AC noise. type:3.5mm Voltage: AC100-240V Plug Type:EU Plug,it applies to Indonesia, Germany, France, Spain, Italy and so on. Color: Black Material: plastic Package Contents: 1set x Microphone Preamplifier 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.