The Siemens 5SL3425-7MB is a SENTRON 5SL3 miniature circuit breaker — a 4-pole (4P) unit with a C tripping characteristic, rated 25 A at 400 V AC. It protects final circuits in residential and infrastructure installations, clearing faults up to 4.5 kA.
The 4-pole design switches all four phases simultaneously; neutral conductor switching is not built in (: No), so the neutral is solidly connected. Mechanical endurance is 20 000 switching cycles typical — fine for branch protection where the breaker operates infrequently.