Running the Maxitrak Allchin 3/4" Gas fired traction engine, this great little model runs on propane/butane mix in a small tank in the tender burning through a single flue burner in a copper boiler. foot plate mounted displacement lubricator supplies the lubrication. We scaled all parts from an original drawing we found in our archives so it is a proper scale model of the Allchin in 3/4" Scale!