This MCCB's interrupting capacity drops off as system voltage climbs: 121 kA at 240 V, 76 kA at 415 V, 53 kA at 440 V, and 12 kA at 500 V. That 12 kA at 500 V is the figure to check if you're feeding a 480 V panel — it's well within typical utility fault levels for most industrial services, but verify against your transformer impedance and available fault current study.
The 125 A rating holds steady from 40 °C up through 50 °C, then begins to taper: 122 A at 55 °C, 120 A at 60 °C, 117 A at 65 °C, and 114 A at 70 °C. The breaker measures 130 mm high, 76.2 mm wide, and 70 mm deep, with an IP40 front (tools and fingers stay out, but it's not washdown-rated).