That 400 A holds flat through 50 °C — only above 55 °C does it begin to derate, dropping to 385 A at 55 °C and 340 A at 70 °C, so the thermal margin is generous for most panel environments. The interrupting ratings are the headline: 242 kA at 240 V, 187 kA at 415 V and 440 V, 121 kA at 500 V, and 7.5 kA at 690 V.
That 110 mm depth is the overall body — it fits standard MCCB mounting footprints in distribution panels and switchgear cubicles.
Maximum power loss is 98.5 W at rated current. That heat has to be rejected inside the enclosure — factor it into your panel thermal calculation, especially if the MCCB is grouped with other high-current devices.