Yacht Device''s Switch Control YDSC-04 allows viewing of the state and managing four channels of an NMEA 2000 switch bank from the connected buttons with LED indicators. It is designed to work in tandem with Circuit Control YDCC-04 (which contains four latching relays) and is compatible with other NMEA 2000 digital switching devices managed by standard NMEA 2000 PGNs 127501 and 127502.