Radio Shack sells for $30. Used less than 1 year. Price includes shipping. Paypal or money order. This selector enables connection of several digital components to a single receiver. With the four Toslink input/output jacks and one Toslink output/input jack, it is possible to connect up to four digital optical sources to this device. Toslink jacks provide optimum digital signal transfer. Connect CD players, DVDs and other digital components to the selector, then connect the selector to a digital decoder, amplifier or other digital receiver. Just choose one of four components by turning the selection knob.