This sale is for 7mm scale "Manninmodels" model kit of Upnor Castle a Fffestiniog railway Diesel loco in 7mm scale to suit O-16.5 and O-14 gauges.
 
The kit consists of a body, separate roof and cab interior. You will need to source or build your own chassis and of course will require paint, couplers and glue to finsh.
 
The model comes in 2 variants:-
 
Wide, which is specifically designed to fit onto the the popular and cheap Hornby 0-4-0 train set chassis and the axles are set to suit the Toy train chassis wheelbase of 31.5mm.
This version is 46mm wide- At a scale 6'6"about the same as our Isle of man Beyer Peacocks or the Welshpool and Llanfair.
 
Scale, This is too narrow to fit the train set chassis and you will need to build or supply a suitable chassis that will fit it, such as the one made by https://www.locosnstuff.com/ that is specifically for our model.
The Scale version will fit 16.5mm wheel sets with the frames being 23.5mm apart. The inside of the bonnet where the motor goes  has a width of 19mm and the wheel base is a scale 36.5mm.