These five four-wheeled wagons were built by the Railway Company using chassis' from the original 1873 four-wheeled passenger stock as detailed below. They were constructed as there was a requirement for vehicles that had lower sides than the standard "H" and "M" classes and were used for carrying mackerel and smoked herring to a maximum load of three tons, being commonly transported in baskets and barrels.

They were 17' 6" long and 5' 10" wide and featured a central drop section for access and this consisted of a single plank that slotted between two metal guides with no form of fastening and this was 4' 9" wide, with low sides of only 1' 3". They were allocated fleet numbers, the wagons simply being labelled "Fish Wagon" along the left side in white paint with black shadowing, whilst the far right side of the vehicle carried the number, though there were many variations on this.

The metalwork was painted black and woodwork mid-grey.  The accompanying image, although a poor study of the class clearly shows the numeral and proportion of these wagons in comparison to Mr. 40, seen at Peel Station.  Click on a link below to learn more about each individual wagon:-