What this 1A D-curve 1P+N MCB covers
At 230 V AC the interrupting capacity hits 50 kA per IEC 60947-2, with a 15 kA rating under EN 60898 for domestic-style distribution boards. For DC circuits the breaker is rated 72 V max, 15 kA per IEC 60947-2. The 1P+N layout lets it disconnect the neutral alongside the phase, which matters when the neutral is not a solidly bonded bar — common in industrial sub-panels or where the supply transformer is local.
That is well above the typical 10–25 kA available fault current on most secondary-side distribution, so it gives selectivity headroom upstream. The 15 kA per EN 60898 is the lower domestic/commercial rating; the 5 kA per UL 1077 and CSA C22.2 No. 235 covers North American supplementary-protector applications. If you are coordinating with a larger upstream MCCB, the 50 kA figure lets you use a lower-rated main breaker without worrying about cascading failure.
The combined terminal at top and bottom accepts copper conductors; the breaker is sealable for metering applications.