The General Steam Navigation Company (GSN) bought a majority shareholding in the New Medway Steam Packet Company in 1937, although the NMSPCo. Continued to trade under its own name. The models commemorate that event in the life of Medway Queen.

These models are based on the long wheelbase Dapol N gauge 20ton mineral wagon in a fictional “General Steam Navigation” livery. It has been produced in two body colors with running number 23 to mark the year of introduction of these models.

The models were commissioned in cooperation with the General Steam Navigation Locomotive Restoration Society.