The ABB XT4XU3250BJL40CXXX is a 3-pole breaking part from the XT4X 250 frame, listed with UL/CSA approvals. This is the interrupting section of a molded-case circuit breaker — the part that opens the circuit under fault — specified when the breaker's internal mechanism or trip unit is already in place and only the breaking assembly needs replacement.
Mounts into the XT4X 250 molded-case breaker frame. The '3P F F' designation indicates three poles with front-connection terminals (F F) for panel wiring. UL/CSA listing confirms acceptance in North American panels without additional agency review.