Using LM386 amplifier chip, magnification of 200 times, you can directly drive small power speakers, suitable for electret microphone amplification.
Practical application: Deafness hearing aids: board connected to the microphone, power, headphones, is a good deaf hearing aids.
Operating Voltage: DC 3.7V-12V
Board Size(approx): 25mm x 25mm
Packing List: 1pcs x LM386 Electret Microphone Power Amplifier Board