This small but surprisingly powerful amplifier is ideal when you want to connect speaker to a MP3-player or other devices with a headphone output. The power stage can drive large speakers as well, this will enable you to enjoy the full stereo sound quality. A 9 Volt battery is used to supply the amplifier. This kit contains SMD-parts, the battery is not included. Specifications: Output power 2 * 1 Watt Output impedance 4 - 8 Ohm Input impedance : 2 * 75 Ohm Operating Voltage 9 Volt DC PCB size : aprox. 38 * 50 mm² This amplifier is also available as a kit !