From Crutchfield Construction: black metal chassis padded feet 100 watts per channel continuous power handling Flat frequency response from 20-20k Use 4-8 ohm speakers Tech Notes:The SPS6 connects all speakers in parallel and the button on the front of the unit adds 3 ohms of resistance to the total load. Ohms law can then be applied to determine the operating load of a given combination. For example: when 4 pairs of 8 ohm speakers are used with this selector's built-in impedance correction circuit, the amp will see a 5 ohm load. If you use 4 pairs of 4 ohm speakers, the total load drops just below 4 ohms. In this case be sure your amplifier can handle a 4 ohm load.