The Siemens 5SL6025-6MC is a 1+N pole miniature circuit breaker (MCB) with a B tripping curve, rated 25 A at 230 V AC and a 6 kA breaking capacity. It's a basic-device class breaker from the 5SL6 series, meant for final-subcircuit protection in residential or light commercial panels.
That suits lighting and general-purpose socket circuits where inrush is low. The 1+N pole arrangement switches the line conductor and breaks the neutral, but the neutral pole is not overcurrent-protected — it just isolates. That's standard for single-phase final circuits in many markets.
Product class is B: return restricted, so Siemens directs you to contact your Siemens partner or distributor for ordering. That's typical for breakers — it doesn't mean hard to get, just that the channel handles it directly.