Its 4.5 kA breaking capacity per EN 60898 and IEC 60947-2 at 400 V AC means it can safely interrupt fault currents up to that level — adequate for most sub-distribution boards where the prospective short-circuit current stays under that threshold.
The C-curve trips between 5 and 10 times rated current — 30 to 60 A for this 6 A unit — making it the right choice for circuits with moderate inrush, like small motor loads, lighting banks, or transformer primaries. A B-curve would nuisance-trip on the same inrush; a D-curve would let a fault run too long. At 6 A it protects a branch circuit feeding, for example, a handful of contactors, a small control transformer, or a lighting sub-panel. The IP20 rating (with conductors connected) is standard for enclosed panel-mount — no special sealing needed inside the cabinet.
Mounting position is any. Halogen-free and silicon-free construction matters in environments where off-gassing from a fault could corrode nearby contacts or sensitive electronics — a real concern in cement plant control rooms with exposed relay contacts.