heuer lemania 5100 "vintage 1983" it says in the ad - I can't find a similar watch anywhere. Has it been extremely polished or what is this?
Not knowing much about Heuers, I'm going to jump in and say that is a ticking time bomb of trouble. With no other Heuer markings except the dial, I would be very leery. Any pictures of the bracelet clasp? Googling 045 end links comes up with Rolex hits for a 7206 bracelet.