This is a fascinating watch. Is it a "2000 Aquaracer?" As in, before the line became simply "aquaracer?"
No, the 2000 became the Aquaracer in 2005 IIRC, this is the Aquaracer Chronotimer from about 2008 or thereabouts. It is from the same Aquaracer family as the Calibre S and other models with the split bezel (CAF) It was also available in a yellow dial, perhaps to attract Breitling Aerospace customers... but personally I think the yellow looks a bit rubbish because of the curved upper display (the yellow Calibre S is awesome though).
You can pick these up fairly easily for about £1000.
When I say 'split bezel' the black ring on the inner part of the bezel is fixed tachymetre, while the outer part is a rotating diving bezel. Pretty cool!
Yep, I had (finally) resolved to sell my custom DLC Speedmaster since I never wore it, and wouldn't you know this came up the very same day! It's always hard to sell a chrono but it's not so bad when you immediately get another in 😁