The ISS8 High Power Speaker Selector is an easy and effective way to distribute music to up to eight listening zones (four pairs of speakers) and play any pair, a combination of pairs, or all pairs simultaneously. Easy to connect with a low-profile design that easily fits into a cabinet or equipment rack.n choose. Front-panel push buttons let you quickly turn each pair of speakers on or off independently, and die cut labels fit within the recessed area on the buttons for easy labeling of each zone. A passive device that does not require power to operate, the ISS8 also includes impedance-matching circuitry so you can safely drive all eight pairs at once without damaging your receiver or amp. Designed with quality in mind, the ISS8 is constructed of 16-gauge steel with a durable black powder coating and gray silk-screening.