It's a 3-pole unit rated 25 A continuous at 40 °C, with a breaking capacity of 121 kA at 240 V AC — that's the number that tells you it can handle serious fault currents without blowing apart.
Breaking capacity — the real story
This MCCB's interrupting rating drops as voltage rises: 121 kA at 240 V, 75.6 kA at 415 V, 52.5 kA at 440 V, and 11.9 kA at both 500 V and 690 V. The 121 kA figure at 240 V is what you'd see on a 480Y/277 V panel's secondary side; the 11.9 kA at 690 V matters for industrial drives or mining gear.
Rated current holds at 25 A from 40 °C up to 50 °C, then drops to 24 A at 55–60 °C, and 23 A at 65–70 °C. That's a shallow derating curve — good for panels that run warm. Maximum power loss is 11 W, which is modest for a 25 A MCCB; it won't cook adjacent components in a tightly packed DIN rail enclosure.
Factory-fitted with 2 auxiliary switches (HQ design) and an undervoltage release (UVR).