VANCO SS4 Speaker Selector Box 4 Pair StereoPN VAN SS4 * VANCO SS4 SPEAKER SELECTOR Low profile speaker selector unit that allows for distribution of high level (amplified) stereo signals into four zones. Features a manually activated impedance protection circuit that can be activated to prevent the impedance to a receiver, this protection keeps the receiver from dropping below 5 Ohms, regardless of the impedance rating of the speakers utilized Impedance protection can also be de activated,