The 2-pole design switches both phase and neutral on a single-phase circuit, or two phases in a multi-phase system. With a maximum operating voltage of 440 V AC multi-phase, it's suited for 400 V three-phase distribution boards where you need to protect a single-phase tap or a two-phase load. The 72 V DC maximum rating means it can also serve in some DC circuits, but the DC breaking capacity isn't listed — treat that as a derating case and verify coordination with the upstream fuse or breaker. Thermal derating is baked into the spec: the breaker carries 50 A at 30 °C ambient, but drops to 46.19 A at 40 °C, 44 A at 45 °C, and 39.81 A at 55 °C (–). The 10 000 mechanical switching cycles is typical for this class; it's not a high-cycle motor-starting contactor, but fine for normal branch-circuit switching and fault interruption.
The 5SL6250-7BB snaps onto a standard 35 mm DIN rail per EN 60715, occupying 2 modular width units (36 mm wide,). It's sealable, meaning you can lock the toggle in the off position with a padlock hasp for lockout/tagout. The halogen-free and silicon-free construction is a plus for environments where outgassing from a fault could damage sensitive electronics or contaminate cleanroom processes.