This is actually two wagons made into one. The steel underframe was built in 1903 by Hurst Nelson, Motherwell, part of tank wagon No.7 for William Baird & Co. Baird's later rebuilt it as an open engineer's breakdown wagon which was used at Gartsherrie Ironworks. In this form it came into SRPS possession in 1968, and can be seen in the picture of CR Brake Van no.437.
The date of construction of the salt wagon body, and its builder, are unknown. The body was recovered from a farm near to Hawick, where it had served as a hay store for sheep. On one side, the original Saxa Salt colours and lettering could be made out, and have been recreated. The number is the original one. These colours are well known from the Hornby model.
The wagon represents a once-common type. Salt was (and is) mined in the area around Middlewich in Cheshire, and transported from there to all parts of the country.