The ABB XT7HQ312EFFF000XXX is a 1200 A three-pole circuit breaker from the XT7H family, fitted with an EKIP DIP LSI electronic trip unit. The description is XT7H 1200 EKIP DIP LSI IN1200A 3P F F UL, confirming the 1200 A frame, LSI protection, and fixed front terminals with UL listing.
With a 1200 A continuous rating, expect busbar or cable connections sized accordingly — this is a main or large-feeder breaker, not a branch device. The fixed-front terminals simplify panel wiring and reduce points of failure compared to draw-out versions.