versatility
modular construction
reliability
ease of maintenance
road switcher design
multiple unit capability
turbocharging (on some models)
used in heavy freight service
alternator or generator (depending on model)
cab or hood unit design
dynamic brakes (on some models)
short and long hoods
used in branch line service
used in commuter service (some models)
used in export service
used in heritage railroads
used in industrial service
used in light freight service
used in local freight service
used in mainline service
used in military service (some models)
used in museum collections
used in passenger service (some models)
used in switching service
used in tourist railroads
used in yard service
walkways along both sides