In 1940, the Pennsylvania Railroad, pleased with both the General Electric 44 ton centercab switcher and the center cab P5A locomotive, decided to order a heavier center cab road switcher. General Electric obliged with a 1,000 HP locomotive, essentially a stretched version of the 44 ton centercab. Since the primary operating area of this switcher was to be on the Northeast Corridor, the Pennsy ordered the switchers equipped with a center pantograph for operating under catenary as well as using the diesel engine when not under wire.
The GS10-DE (General Electric, Switcher, 1000 Horsepower, Dual Electric) turned out to be a smashing success, doing equally well in switching coaches, pulling local freights and, on occasion, powering commuter trains as far afield as Paoli, Trenton and New York City. Robust and well built, these road switchers outlasted the Pennsy, Penn Central and Conrail, with examples still surviving on short lines to this day. One such line, the Razorback Traction Company, has restored its GS10-DE to original Pennsylvania Brunswick Green livery:
Anyhow, that's my story, and I'm sticking to it. 
It do look snappy with the painted guardrails and steps! And the Lionel pantograph does have a power lug attached if I wanna wire it for live overhead.
It's gi-raffe approved!
Mitch
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