The Schneider Electric A9R84263 is a 2-pole residual current circuit breaker (RCCB) from the Acti9 iID range, rated at 63 A with 300 mA earth-leakage sensitivity. The voltage-independent trip mechanism means it clears a ground fault even if the line voltage collapses, which is the standard for this class of RCCB.
The 63 A continuous rating (In) matches the main feeder or sub-feed in a residential or light commercial distribution board. The 300 mA sensitivity is a common choice for whole-building or sub-main protection where nuisance tripping from normal leakage (cables, surge suppressors) must be avoided — it is not for personal shock protection (30 mA or lower is the rule for socket-outlet circuits). The rated insulation voltage (Ui) is 500 V AC, which gives headroom for the internal clearances.
Neutral is on the left. The outgoer position in the panel is typical for an RCCB feeding downstream MCBs or a sub-board. The IP20 body is fine for enclosed panels; the modular enclosure carries IP40 when installed in a compatible enclosure.