amanico[JLC Moderator]
405341
Some answers
The code number is :
XXX refers to the model.
XX, to the material use for the case and the strap / bracelet.
The last 2 XX refer to the color of the dial.
It is not the first time I see a difference in the reference number between the catalogue and the watch in itself.
The Master Date has been released in the mid 90ies, to be discontinued in 2006.
It had a very nice " ancester " from the 40ies, the Triple Date, ( Credit pic: Dino ) :

Hope this will be of some help for you.
Best,
Nicolas
Some answers
By: amanico : November 3rd, 2009-01:48
The code number is : XXX refers to the model. XX, to the material use for the case and the strap / bracelet. The last 2 XX refer to the color of the dial. It is not the first time I see a difference in the reference number between the catalogue and the wa...
You know what, David?
By: amanico : November 3rd, 2009-06:54
I tend to agree. But it is just our taste. I much prefer the cool and, to me, more elegant look of the former Triple Date, closer to the Vintage than the latest one. Like you, I'm not a big fan of the large power reserve under 12... Best, Nicolas