Oliver is a green Great Western tank engine.
- Oliver with Branch Line Coaches (Plarail, Tomica World, Thomas Motor Road and Rail, TrackMaster [Tomy])
- A prototype Oliver features a different face and an unpainted cab doorway.
- Oliver has black wheels, which he happens to have in the Railway Series.
- Oliver, along with Etienne, are the only engines never to be released in the US.
- Oliver's side-rods are mounted between the first and second wheels. Oliver and Stephen are the only engines with this arrangement.
- Oliver's drive wheels have holes in them, although his side-rods do not connect to them. It seems likely that Oliver was originally intended to have his side-rods connected to his drive wheels, but they were instead mounted to his middle wheels so as to look more like the actual character.