Uses an NCP2890 audio amplifier IC chip that can output 1W of power and an 8ohm 66mm speaker. Product Contents: Apmlifier PCB, battery cage, 8ohm speaker, 3.5mm mono jack lead, 2x 1uF capacitor, 1x 100nf capacitor, 1x 100K resistor, 1x 15K resistor.
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