The first bezels fitted to the 2915’s were engraved metal ones that I know very little about. They are so rare even the ones that look old might be fakes.
Then a black BASE1000 bezel was fitted to the 2915-3 and the 2998-1 and 2998-2. These command huge prices, and the last BASE1000 bezel I saw sell achieved about $6000, though as of October 2016, I know of collectors willing to spend up to $10,000 for a top example.
There are only two correct BASE500 bezel designs originally fitted to the 1960’s watches, and then there is a later service bezel that is often seen, distinguished by noticeably smaller TACHYMETRE letters.
There are also minor font differences seen within these three designs, perhaps different manufacturers – but for the purposes of value however these are three you are likely to see. The oldest is at the bottom, and the modern, incorrect for our range, at the top:
- The Dot Over 90 fitted 1961 to 1969 (DO90)
- The Dot Next To 90, with tall TACHYMETRE letters. 1968 to 1978 and beyond. (DN90)
- Later, small TACHYMETRE letters. Similar to the current model. This is never correct for the pre 1978 watches I cover.
There is also the 220 misprint bezel fitted to some 31m serials. Very rare, and more interesting than valuable.
The DO90 bezels recently started trading at the $800-$3000 level, so this has a significant influence on the value in a watch.
Bezels are a service part, and they are as easy to change as your socks. Well, taking off is surprisingly easy. And putting the bezel back on the same watch it was removed from is mostly straightforward.
Putting them back on can be tricky – Nothing is ever simple with watches, and sometimes a different bezel will not go on a different case. I believe all the case sizes (post 2915) are the same but I have found some variations.
Sometimes the bezel goes on too easily and could fall off in use. When I replace a bezel I check the fit with my fingers – I try hard to pull it off – and then I check with a loupe to make sure there is not a gap.
Any problem I have had, has always been resolved at the workshop where the people who actually know what they are doing work. This was the case with these two watches:
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