The C curve means it's designed for moderate inrush loads — think small motor circuits, lighting banks, or general-purpose distribution where the start-up current isn't extreme but exceeds a resistive load's draw.
Where it fits — panel and environment
At 36 mm wide (2 modular units), it occupies two adjacent slots in a consumer unit or sub-distribution board. Mounting position is unrestricted, so you can orient it any way the panel layout demands.
Thermal derating — the number that matters for real loading
At 40 °C it derates to 37.72 A; at 50 °C it drops to 35.3 A. If your panel runs warm — and most enclosed distribution boards do — the actual continuous current you can pull is lower than the label. The C-curve magnetic trip still holds its multiple, but the thermal bimetal element responds to the temperature it sees. Factor this in when sizing for a continuous load near the limit.
Halogen-free and silicon-free construction, which matters if the breaker lives in a clean-room or semiconductor-adjacent environment where outgassing can contaminate optics or sensitive surfaces.