The Hoppers are used for transporting large amounts of bulk material such as coal, ballast and stone. They are commonly used for construction on Sodor, such as when the Harwick Branch Line was being built. During that time, several hoppers of ballast loads were seen in the construction yard. Hoppers are mostly used at quarries or mines.
The hoppers are based on British Railways' ZFV 'Dogfish' ballast hoppers and BR 22 ton iron ore hoppers. Hector is based on ICI Hoppers.
The hoppers come in many liveries, such as gold, brown, grey and black. The most common livery of them is the North Western Railway's standard grey trucks livery.
- To date, Hector is the only hopper that has been named and seen with a face. Also, he was originally going to be called "Hopper".