This is the EMD GP9M Standard DC Chessie System #5978 Yellow, Orange, and Blue in HO Scale by Walthers Trainline.
The Electro-Motive Division (EMD) of General Motors was the last major builder to enter the road switcher market, introducing the GP7 (GP for General Purpose) in 1949. In 1954, the more powerful GP9 was unveiled with a 1750 horsepower prime-mover. This became the most successful of the early geeps, with sales of more than 3,800 locos in the U.S. and Canada. As the GP9s were bumped from major freight and passenger trains by newer locos, they began new careers as switchers. Many roads rebuilt them with a low nose to improve forward visibility and they continue to serve in switching, wayfreight and transfer assignments today.
This model will be a real workhorse on your model railroad, with great features like a heavy die cast metal frame, powerful can motor with flywheel, eight-wheel electrical pickup and drive, and a working headlight. Fully assembled and ready for service, they come prepainted in a variety of schemes.