Classicwatch Vintage Watches

Merry Christmas !

I recently picked up an 18K LeCoultre that I am having difficulty finding information on. It is an early Bumper automatic with 476/2 movement.

Luckily in this forum I found the thread below (Early bumper automatic) with the pictures nearly identical except that mine also has "Automatic" written below LeCoultre on the dial.

viewtopic.php?f=6&t=678&p=1132&hilit=bu ... atic#p1132

I am having trouble finding out what the reference numbers mean inside the caseback.

There are two sets of numbers.
386 C 307
131xxx (which I believe is the serial ?!)

Here is a wrist shot:

I'm not sure what that is either...if you could maybe provide a photo of the inside of the case back. Thanks.

Not the best of pic but here it is..
I appreciate your help.
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