Last Saturday I was handed this: It's of around 7mm scale and in the photo is standing on Peco HO track. But what is it? That I didn't know. Jacky Molinaro came to the rescue with some prototype information: Petolat, built 1930, a 'test' production run of one, retired from work in the 1950s. Jacky also supplied this in service photo:
But what is the kit and who made it? It's nominally 7mm scale or Oe and of etched brass construction.