That means what you order is what protects the circuit; no field tweaking the trip curve. Breaking capacity hits 121 kA at 240 V AC, dropping to 75.6 kA at 415 V, 52.5 kA at 440 V, and 11.9 kA at 500 V and 690 V — so it handles high-fault scenarios on the low-voltage side and still clears at 690 V.
Rated 16 A from 40 °C up to 55 °C ambient; derates to 15 A at 60–70 °C. That's a real constraint for a panel OEM pushing fill factor. Power loss is 10.6 W maximum at rated load. Small enough that ventilation isn't critical for this one breaker, but in a dense panel with a dozen of these, the heat adds up.
Panel fit and protection class
The 4-pole width (101.6 mm, or 4 inches) is standard for a 4-pole MCCB — it'll drop into a panel cutout designed for a 4-pole SENTRON frame without surprises.
If you need those add-ons, you're looking at a different variant in the 3VA family. Trip indicator is also absent; you'll know it tripped only by checking downstream load or the handle position.