ABB XT5XU360BBFF000XXX is a 3-pole breaking part in the ABB XT5X series of Molded Case Circuit Breakers (MCCB). Marked as F F for the frame and trip unit configuration, it carries UL/CSA and TU approvals. This is the exact breaking assembly — the interrupt-capable core you'd swap during a recondition or if the old unit tripped hard and lost its calibration.
The '3P' tells you it's a three-pole device — standard for three-phase distribution. 'F F' stacks the frame code and the trip unit code; in ABB's XT5X naming, that first F is the frame size, the second F is the electronic trip unit variant. UL/CSA listing means it's accepted across North American panels without a special inspection. TU (Türk Loydu) adds marine-class certification for shipboard switchboards.