Help with ID please?

From what I'm reading the numbers on back should have more letters? Is one of these a serial # or are those inside? An older gentleman has asked me to sell this & some other things for him on ebay, which I'm happy to do, but I like to be halfway knowledgeable in my descriptions. Also I'll be happy to share the ebay link here if any one is interested when it goes on auction, and that's permissible. I've read that one shouldn't post photos of serial #'s, is that true? Basically just asking what to call this model, saw similar being called Divers? and is it early '90's? Thanks in advance!

Well, first off, it's genuine, and in reasonable condition except for all that gunk on the caseback! The model number is on the back - S90.813K and this is a Tag Heuer S/EL Professional. Size is 33mm. It could be classed as a dive watch and is water-resistant to 200m, although it should be pressure-tested before doing that given it's age! Age-wise, you're probably about right, but check the catalogues on this site if you want to be more precise.

Key question - does it work, or does the battery need replacing? If an old battery has been left in, then you ought to replace it in order to establish if the movement is still functioning before selling. Also, don't forget to list the size of the bracelet - it's possible it's been sized to fit a smaller wrist and some links might be missing.

Oh yes, you also asked about posting the serial number or not. Well, for starters, you already have (in your photo of the caseback)! I don't see that as a problem, though. Some people believe it makes it easier for watch fakers and fraudsters to use that number in a genuine sale, or when making a fake. As if they really need one, or couldn't easily find out a random serial number some other way. I think it might stem from people blanking out registration plates when they try to sell their car in order to avoid their number plate being cloned. Not sure the same logic really applies to watches, though.

Thank you kindly for your reply! So the number going vertical is the serial then? I can alter the photo, but I left it all clear because I wasn't even sure which one it was, if either. I think it's kind of silly, but I like to do what is most acceptable. I was pretty sure it was genuine and the owner I believe has had it since new, I'll have to ask. Also it has a broken leather band, which isn't original to the watch, but a TH stamped leather band is in the case, but alas no buckle. I'll have to get a battery installed to see if it still works. I'm in the boonies, surely there is a jeweler here who will be able to remove the back & clean it up a bit while they're at it. Thanks again!

Yep!

I meant here in town, not on this site re: the battery. 🙄