A small and useful device that amplifies the microphone signal to line level. 
It accepts dynamic and condenser microphone with internal supply. 
The circuit is based on the integrated circuit NE5532 that ensures low noise,
low distortion, high sound quality and reliability. 

           FEATURES:
Supply Voltage : 9-24VDC max. (Can also be operated with a 9V PP3 battery).
Input Impedance: 10 - 47 Kohms at 1kHz.
Output Impedance: 47 Kohms (200 Ω min).
Input sensitivity: 2-10mV.
Output: 300mV (1.8V max).
Gain: 40db
S/N ratio: >85db.
Frequency Response: 20Hz to 20kHz +/- 0.5db.
THD: <0.05%.
Metal film Resistors and good quality capacitors.
You can use any GOOD POWER SUPPLY YOU HAVE WITH VOLTAGE 9 TO 24VDC/100mA min.
Dimensions (WxHxD): 38 x 39 x 9,0 mm.
Colour:  Blue or Green.
5 Years Warranty.