This circuit is a compact desin AF amplifier based on the TBA810 Integrated Circuit. Its low consumption and compact dimensions make it ideal for all kinds of audio amplification applications. The circuit incorporates an overload protection circuit and volume control. In addition, the circuit has low/high impedance inputs that can be connected to any audio source. Supply voltage: 12-16V DC @ 0.5A. Recommended adapter: RP-1240R-P. As kit contains solder it may not be available for purchase in California.