The F-Unit is probably the most recognized diesel locomotive in North American history. It was found on railroads from East to West and North to South. The second generation of EMD's F-unit series was, unsurprisingly, the F2, following on the manufacturer's success with the original "FT" locomotive. It was common for railroads to use these two locomotive series' together when operating them for freight services.
The Kato EMD F2 + F3 come in both A and B (cabless) variations. All Kato F units have DCC friendly mechanisms and all units (both A and B) are powered. These locomotives come packaged in pairs of powered units in a manner which the prototypical railroads would have used them.