OO Gauge 4mm Scale Victor Electric Tractor Listing is for a pack of 3 Tractors 3d printed in resin. Tractors like this were found at factories, depots, railway stations and military establishments for moving goods and supplies around the site. Similar examples to this were around during WW2 and were certainly around for decades post war. I have drawn this model from measurements taken from a prototype sitting in a local reclamation yard. Just add wheels, couplings to complete. This model is based on an original design by Jonathan Duffet.