I saw these at a trade show recently, and they seemed like they would make a good, easy, project for the tinplater. Not quite O gauge, the wheels are just a tiny bit too far apart, as can be seen in the second photo. Taking them off & just snipping a little off, will bring them right into gauge. Powered by a traditional clockwork motor, and constructed of lithographed tin. Sure, they're not in the same league as the MTH or Lionel tinplate, but for an inexpensive nostalgia trip, these are hard to beat! Measures approx 6 1/2" long, 3 1/4" tall, 2" wide. The last photo shows it in comparison to a Lionel O27 locomotive, so you can get a better feel for the size.