Auxiliary switches report the status of the main devices on which they are mounted. The DRCBO 4 Hi 1 auxiliary switches are suitable for FI/LS combinations of the FIB and FIC series in the type A 3+N and type B versions. The operating status of the circuit breaker can be displayed using signaling devices. Properties: Auxiliary switch function, signal switch function, can be retrofitted, small size, type of installation: to the left of the base unit using screws, quick fastening to the mounting rail, any installation position, areas of application: These devices are suitable for querying the operating status of power supplies in residential and commercial buildings as well as industrial plants. Notes: The auxiliary switch does not affect the function of the base unit.