The 4.5 kA breaking capacity per EN 60898 and 5 kA per IEC 60947-2 cover most residential and light-commercial panel fault levels; for higher SCCR you'd step to the 5SY series. Derating is already baked in: at 40 °C ambient the breaker carries 38.07 A, at 45 °C it's 36.8 A, and at 55 °C it drops to 34.97 A. If your enclosure runs hot, size the load side accordingly — the 40 A nameplate is only good at 30 °C. For a 3-pole unit that's 9.9 W total — factor that into your enclosure thermal budget when ganging multiple breakers.
Mounting position is unrestricted, so you can lay it sideways in a shallow enclosure if needed. Sealable design allows locking in the OFF position for lockout/tagout. Halogen-free and silicon-free construction — no corrosive off-gassing if the breaker faults in a sealed cabinet.
Compliance and approvals
Energy limitation class 3. The breaker is marked per EN 61346-2 and IEC 81346-2 function code F. Suitable for residential buildings and infrastructure.