Age of Mamiya 645

I just received my other Mamiya 645 today. Is there a way to tell the year and month of manufacture of these cameras? Thanks

 

Here's a link to Camera-Wiki:

Mamiya M645 - Camera-wiki.org - The free camera encyclopedia

It doesn't provide a great deal of detail, other than when the M645, 645-1000s. and J models.

 

Thank you Dennis, but I was looking for age based on serial numbers. Mine are Supers that from what I understand are from 1985. Thanks again.

 

Actually, the condition is WAY more important than the age. While most of the Mamiya 645 accessories, especially lenses, are interchangeable on all Mamiya 645 models, some things like focusing screens are different, so you have to be aware of that.