Hager 6kA RCBO - Compact
RCBO (Residual Current Circuit Breakers with Overcurrent Protection) devices are a combination of an RCD (Residual Current Device) and MCB (Miniature Circuit Breaker) in one.
An RCD detects Earth Leakage, i.e. current flowing where it shouldn’t, switching the circuit off where there is an Earth fault current. The RCD element of the RCBO is there to protect people.