Tudor Chrono link?

[NKflyer]

Here is a link with some info that should help.

http://tudorcollectorsite.blogspot.com/p/chronos.html

The 942xx and 943xx were the first auto winding Tudor chronos and earned the nickname "big block" due to their thick case. The last two/three digits of the reference number were variable depending on the style of bezel.

A little later, the reference number was changed to 791xx with little to no change in the watch itself. Still considered "big block". Same deal with the last two digits denoting the bezel option.

The reference 792xx is a completely different case, slimmer and more curved. Many were branded "tiger" for the affiliation with Tiger Woods. These are not as collectible as the big blocks.