BG NEXUS WHITE MOULDED ROUND EDGE DUAL SURFACE PATTRESS 37MM SURFACE BOX. BG RCBO CIRCUIT BREAKER DEVICES Single Pole 45A 50A 55A 30mA Type AC RCD Curve B. BG RCBO CIRCUIT BREAKER DEVICES Single Pole 45A-55A 30mA 6kA Type A RCD Curve B.