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 bass is 15dB. With a ow-cut switch. Signal attenuation 80HZ improves speech intelligibility and reduces microphone . With an overload indicator light. The indicator light will 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 will produce AC noise. Colour:black Material:plastic type:3.5mm Package Contents: 1 x Main unit 1 x DC cable 1 x male to male cable 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.