It's the kind of breaker you spec into a main feeder or a big motor branch circuit where you need serious fault interruption — 440 kA at 240 V, 330 kA at 415 V and 440 V, 220 kA at 500 V, and still 52.5 kA at 690 V. Those numbers aren't just for show: they tell you this breaker can clear a bolted fault at the main switchboard without the arc flashing over, which is what keeps the rest of the gear upstream from taking a hit. The continuous current rating holds flat at 400 A from 40 °C up to 50 °C, then starts to derate: 385 A at 55 °C, 370 A at 60 °C, 355 A at 65 °C, and 340 A at 70 °C. The 96 W maximum power loss means you size your enclosure ventilation accordingly; it's not a huge heat load for a single breaker, but in a dense lineup it adds up.
IP40 front protection. That covers most industrial plant conditions — cold warehouses in winter, hot motor control centers in summer. The part accepts an optional motor drive for remote charging, which is handy if you're automating breaker reclosing in an unmanned substation.