Pig iron wagons were used for the transport of heavy pigs from iron works to foundries or steel making plants. Their main area of activity was the industrial heartlands of Scotland. However when the need arose they were used for general merchandise traffic such as barrels, bales of wool or cotton etc. Because of the portage interests of the NBR at a number of Scottish ports, such as Glasgow, these wagons were seen carrying goods to destinations nationwide. Photographic evidence exists of baled wool traffic from Glasgow to Bradford for example.
The kit represents a pig iron wagon of 14T capacity introduced in 1904. Diagram 82 was dimensionally similar to the 8T diagram 29, introduced around 1896, but with uprated springing arrangements. None of the pig iron wagons required the load to be secured as friction retained the heavy pigs in place. These wagons would have generally had a life of over 30 years and 18 survived to nationalisation in 1948.