Also called the coal car, the tender is assigned to its locomotive at manufacture. Although we perceive them as one assembly, the engine and tender are two separate units of rolling stock. Each has its own identifying number though the only time they are separated is during heavy maintenance or repair. Tenders and engines are not easy to pull apart, because they are linked by a bolted drawbar instead of a coupler.
Quick facts
Tank engine option
Tenders in England
Tenders in United States
Another alternative