The interrupting capacity hits 187 kA at 240 V, 121 kA at 415 V, and 75.6 kA at 440 V, so it can handle high-fault scenarios downstream of a large transformer without cascading upstream.
Ratings that drive the fit
The 125 A rating holds flat from 40 °C through 50 °C, then derates to 122 A at 55 °C, 120 A at 60 °C, 117 A at 65 °C, and 114 A at 70 °C.
Dimensions are 130 mm height, 76.2 mm width (3 inches), and 70 mm depth — a standard 3-pole MCCB footprint that fits most SENTRON distribution boards.