Immediately below is a watch being discussed on TZ-UK -- http://forum.tz-uk.com/showthread.php?274104-About-this-vintage-Heuer

Here's the analysis of a similar watch (shown below) that Mark Moss posted here on Chronocentric, in November 2010 -- http://www.chronocentric.com/forums/heuer/index.cgi?page=46;md=read;id=39407.

These appear to be two different samples; notice the different second hands and the stain on the running seconds register of the TZ-UK sample.

This seems to be another suspicious watch that just won't go away. Both the case-backs are marked "905"; both movements are unmarked . . . Based on Mark's in-depth analysis, seems unlikely that this one is authentic . . . but I'm not so sure. Perhaps this gray guy is authentic. Further research required.

Regarding this watch, it's another one about which we might say, "genuine or not, it certainly is ugly".

Jeff