Federal Pacific circuit breakers come in many types.
Type NA (wide)
Type NC (Thin)
The type NA (thick) and NC(thin) are UBI(Unique Breakers INC.) listed replacement breakers. The original versions were black with red coloring on the handle. The UBIF versions fit correctly. You can remove a NA (thick) version and replace it with 2 NC (thin) to open up space in the panel. Fully UL tested and approved, SWD (Switch Duty Rated) single poles, and HACR (Heating and Air Conditioning Rated) double pole breakers. 10,000 Amp Interrupting Rating. Compliant with ANSI/UL 489, 10th Edition.
The NB, NEJ, HJF, NEF, NFJ series of Federal Pacific circuit breakers are seen in commercial and industrial applications.
Some Federal Pacific breakers not listed may be available so if you don't see what you need please call 810-742-7444. We may be able to help.