The Schneider Electric Acti 9 iC65 4P 40A 30mA is a 4-pole (3-phase + neutral), 40A, 30mA Residual Current Circuit Breaker with Overcurrent Protection (RCBO). This integrated device combines a high-performance miniature circuit breaker (MCB) and a sensitive earth leakage protector (RCD) into a single compact unit.