Bose Professional ControlCenter digital zone controllers provide volume and source selection for Bose Professional CSP, ESP, and EX sound processors. Powered using PoE, up to 16 units for CSP and 32 units for CSN can be used simultaneously on an Ethernet-based network. Three models are available in either black or white, feature volume/source LED indicators, and fit 1-gang electrical boxes in North America, Europe, and Japan.