What this 2-pole B-curve 25 A MCB does in your panel
The SENTRON 5SQ2260-0KA25 is a 2-pole miniature circuit breaker with a B tripping characteristic, rated 25 A at 400 V AC/DC and a 3 kA breaking capacity per EN 60898. The 2-pole design switches both phase and neutral (neutral conductor switching is built in), so it fits single-phase final subcircuits where you want full isolation on both conductors. At 55 mm installation depth and 2 width units, it occupies standard DIN-rail space; IP20 finger-safe terminals are fine for enclosed distribution boards.