Its description on the product line is XT4S 250 TMF 125-1250 3P F F UL/CSA, indicating a 3-pole, fixed version with a TMF (thermal-magnetic fixed) trip unit rated 125-1250 A.
The TMF trip unit covers a 125-1250 A adjustable range, so the breaker fits applications from moderate feeder protection up to heavy motor or transformer circuits. The fixed (F F) configuration means the trip unit is non-interchangeable in the field — select the right amp range at order time. The XT4S 250 frame is designed for panelboard and switchboard mounting, with a compact footprint that saves rail space compared to older ABB SACE frames. UL/CSA listing confirms acceptance in North American installations without additional agency review.