This model is designed to fit on a 2015 Hornby J15 Chassis, with 13 livery variations being available: C.R. Fitted, C.R. Unfitted, LMS Early Fitted, LMS Early Unfitted, LMS Late Fitted, LMS Late Unfitted, BR Transitional Fitted, BR Transitional Unfitted, BR Early Crest Fitted, BR Early Crest Unfitted, BR Late Crest Fitted, BR Late Crest Unfitted, As Preserved. The CHASSIS IS NOT SUPPLIED with the model.

The Caledonian Railway 812 and 652 classes were classes of 79 locomotives and 17 locomotives respectively. The classes were designed by John F. McIntosh with both classes being virtually identical. The 812 class were built between 1899 – 1900, 29 by the Caledonians St. Rollox works (282 – 293, 812 – 828), 20 by Neilson & Co. (829 – 848), 12 by Sharp Stewart (849 – 863), and 15 by Dübs & Co (864 – 878). The 652 class were built between 1908 – 1909, with all 17 being built by the Caledonians St. Rollox works (325 – 328, 652 – 659, 611 – 665). 17 locomotives were fitted with Westinghouse air brakes for use on passenger trains. All 96 locomotives were absorbed into the LMS in 1923 where they were renumbered 17550 – 17645 and given the power classification of 3F. Withdrawal started in 1946, with 3 locomotives being withdrawn before nationalisation, 17567, 17598, and 17610. In 1948 the remaining 93 locomotives went into BR ownership and were renumbered 57550 – 57566, 57568 – 57597, 57599 – 57610. The remaining locomotives were withdrawn by 1963, with one locomotive, 828, preserved.

Caledonian Railway number 828 (LMS 17566, BR 57566) was built in August 1899 and was withdrawn on the 8th of August 1963. It was bought by the Scottish Locomotive Preservation Trust fund, and was moved to the Glasgow Transport Museum and put on static display. In 1980 the locomotive was moved to the Strathspey Railway for restoration to full working order, and returned to steam in 1993. Since then it has worked primarily on the Strathspey Railway.