This is PAM8403 Mini 5V Digital Amplifier Board With Switch Potentiometer. PAM8403 is a small digital amplifier chip, high-definition sound quality highlights the advantages of digital chips, the circuit using the most reasonable peripheral configuration, power supply filtering is upgraded to 470uf (some sellers are less did not even 100uf capacitance). 1.6mm glass sheet, the real amplifier board did the most detailed, high-fidelity sound output 3W + 3W, is a rare good product enthusiasts amplifier, potentiometer using the original anti-meter body, potentiometer with the switch can cut off the power supply directly counterclockwise.