Every watch has a unique combination of reference model number plus serial number. If your last for digits are 0000 then you have the first watch made for that model reference number.

Returning to our examples and using the second digit from the serial number we get the following production dates: If you were paying close attention you may have noticed we asked for the case code in the form above but we did not mention using it when calculating the date.

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This is also on the case back and is six digits long.

In the example images the serial number is highlighted in blue. For many of Seiko's movements we know the first year they were produced and for most movements they were produced for less than 10 years. Using this additional information we can update our three examples: The remaining four digits of the serial number indicate the production number for the watch.

Seiko SNXS80K automatic gold plated gents watch, has a round case with a gold colour dial.

This trendy lightweight Stainless Steel Seiko 5 timepiece is the perfect accessory for the retro yet modern man.

In the example images the reference model number is highlighted in red.

The other number you will need is the serial number.

As the inventor of the quartz watch in 1969, Seiko has led the watch industry for four decades in refining quartz technology for each new generation. Model: SEIKO Men's SNZH53J1 Automatic 7S36 Movement. Seiko 23 Jewel Automatic watches have the traditionally built mechanical movements same as some of the best known and most e...

The movement of this Seiko watch is visible through the viewing window which is positioned on the back of the...

The beautifully stylish Gents Seiko watch with a black dial and date window.

Men's sports watch from the SEIKO Solar collection...

50m / 5 ATM A watch with this level of resistance is wearable around household sinks, while playing sports and while swimming in shallow wat...