One of the Philadelphia & Reading inspection engines was number 100, built by Baldwin in 1902 as their number 21341. It had a 4-4-0 wheel arrangement and a narrow boiler. The boiler was deeply embedded in the passenger compartment and there were four armchairs on each of its sides. With a heating surface smaller than that of most 1870s 4-4-0 locomotives, it was not intended to haul many additional cars. The locomotive was painted olive green with crimson stripes while the tender was Pullman brown with gold lettering and stripes. The latter had a scoop to replenish the water on the run. In 1913 a new built 4-4-2 inspection engine got the number 100 and this one was renumbered to 102.