At 415 V the rating is 154 kA, at 440 V it is 121 kA, and at 690 V it drops to 17 kA; the buyer must match the interrupting rating at the system voltage, not just the highest number. The 16 A rating holds flat from 40 °C to 50 °C (–), then derates linearly to 14.4 A at 70 °C — per the datasheet, no adjustment needed for panels running up to 50 °C ambient.
The 76.2 mm width is a standard 3-pole MCCB footprint — it occupies three 25.4 mm module positions on a DIN rail or panel-mount base. Front IP40 protection means tools or fingers above 1 mm diameter are kept out, but the enclosure itself is not sealed against moisture — install in a suitable cabinet for washdown or outdoor environments.