Added to OnTheDash – this very early Heuer reference 2403 chronograph, with stepped case and sector dial. The dial originally had radium numerals and markers, matching the radium of the syringe hands, and features the flat (thin) Heuer logo (the full-sized logo would come in the mid-1940s). The 32552 serial number suggests that the watch was produced circa 1935, and the railroad tracks around the registers were often used at this time. Both the bezel and the case-back are stepped. Have a look at the crazy looking, flying saucer (disco volante), UFO style case-back. This is the first one of these that I have seen; perhaps was used on the very first of these models, and then replaced by traditional flat case-back. The case measures 32.2 millimeters across the dial, with a thickness of 10.5 mm (not counting the bulge for the flying saucer). The Reference 2403 is powered by the Landeron 13 movement, and being an early sample, it has a single pusher for start-stop-reset (i.e., no time-out / time-in function). Yes, I love these Landeron 13 chronographs (circa 1935 to 1945) . . . under the radar on eBay and the dealer sites, they are a great way to get into the vintage chronographs. Here is the link for additional photos of this watch and other Reference 2403 chronographs -- http://www.onthedash.com/chronograph/reference-2403-stepped-case-sector-dial-white/