These compact mixer-amplifiers provide 40 watts of output power. Model CC4021 has two (2) inputs: 1 balanced MIC/Line and 1 unbalanced AUX with individual volume controls. Model CC4041 has four (4) inputs: 3 balanced MIC/Line and 1 unbalanced AUX with individual volume controls. They are compatible with 70V, 25V, 4-ohm, and 8-ohm speaker systems. The units measure two rack spaces in height, but are only 8-1/4 wide allowing for two units to be placed side-by-side without requiring additional rack spaces. An optional rack mount adapter is available for single and side-by