Rated 25 A at 30 °C ambient, the breaker derates to 23.75 A at 40 °C and 21.25 A at 60 °C — a consideration when packing multiple units into a warm enclosure. The 4-pole (3P+N) configuration switches the neutral, so it suits TN-S or TT systems where neutral isolation is required.
The closest functional sibling is the 5SQ2670-2YA63, which shares the same 4-pole footprint, 3 kA breaking capacity, C-curve, and 55 mm depth — but is rated 63 A instead of 25 A. If your panel was wired and bus-barred for the 63 A variant, dropping in the 25 A unit is mechanically identical: same 4 MW width, same DIN-rail clip, same neutral-switching arrangement. No rewiring needed at the breaker itself, though the downstream load circuit must be sized for 25 A protection.
Installation depth is 55 mm, so it clears most 80 mm-deep enclosures. For selectivity studies, pair it with an upstream SENTRON 5SL or 5SP series MCCB — the manufacturer's selectivity tables are the reference, not a rule of thumb.