It is sized for 20 A at 40 °C ambient, with a maximum breaking capacity of 52.5 kA at 240 V AC — enough to handle high-fault utility feeds in a distribution panel.
The 20 A rating holds flat from 40 °C through 55 °C (–), then derates to 19 A at 60 °C and 65 °C (–), and stays at 19 A up to 70 °C. That means in a warm panel — say 50 °C — you still get full 20 A; above 55 °C you lose 1 A. Breaking capacity steps down with voltage: 52.5 kA at 240 V, 32 kA at 415 V, 13.6 kA at 440 V, and 7.5 kA at 500 V and 690 V (–).
Width 76.2 mm (3 in), depth 70 mm (2.76 in), height 130 mm (5.12 in) — standard 3-pole MCCB footprint for a DIN-rail or screw-mount panel.