The 40 A continuous rating holds from 40 °C through 50 °C, then derates to 39 A at 55 °C and 37 A at 70 °C — so if your panel ambient runs hot, you still get full current up to 50 °C without stepping up a frame size. Breaking capacity hits 121 kA at 240 V AC, drops to 75.6 kA at 415 V, and holds at 11.9 kA all the way to 690 V AC.
At 101.6 mm wide, 130 mm tall, and 70 mm deep, this 4-pole MCCB fits standard SENTRON mounting feet — direct panel mount or onto a DIN rail adapter. The IP40 front means it is protected against tool entry and >1 mm particles; it expects a closed enclosure in a typical panel.