Another 7C43.

The stamp "B0310" most likely refers to the last battery change.

that makes sense to me too Mario-d

Ahhhhh, sounds plausible. Just the other number now. Thank you for your help!!!!

Regards
David


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B = battery change
first 2 digits = the month
last 2 digits = the year

I would have to agree that it is a date stamp since 03/10 is 10 years past the end of the stock battery change markings on the caseback.

I would think this would only be done if the watch was used in a commercial dive environment as the average desk diver would be oblivious to what the marking on the caseback mean

mmm strange. I have a 7C43 with similar marking s B0804

But they don't look hand stamped to me - the typeface is bigger than that of the serial numbers - but the alignment of the characters , positioning and neatness, imply that they are machine stamped. Wonder if they were added by Seiko for some reason

The subject was also brought up here:

http://forum.tz-uk.com/showthread.php?110085-Seiko-7c43-Query