That is not a ITE breaker, its a Crouse-Hinds and that is handle locking device, and the only I-T-E breaker I see is the one on the upper right row, the rest are GE or Crouse-Hinds, I doubt you could find any paperwork that they are UL “Classified” in a I-T-E loadcenter.
BTW I-T-E is now Siemens, and Crouse - Hinds is now back to their original name Murray, also owned by Siemens, they dropped the Murray/Crouse-Hinds breakers and rebranded I-T-E breakers as Murray,but have seen no paperwork stating I-T-E / Siemens and Murray is interchangable, if anyone has something that says it’s OK, I would like to know.
Well going beyond that…notice the breakers on the right ( GE to be more specific ) does not fit properly into the KO area for the breaker…causing the breakers to sit back into the enclosure.
When Cutler Hammer ( Eaton®) got the " Classified " breakers approved for use in ITE and other enclosures this was critical…to work in the panel it has to SEAT in the panel properly…
Just as a tip…if you see a breaker in an enclosure that is not fitting properly chances are it is not listed for installation in that enclosure…