Google - what info Google wants for ALL products
Basically, Google wants the following information on all products.
Google calls this combination of data the Unique Product Identifier
For some products, Google requires an actual UPC code or an ISBN number instead of just a Manufacturer-Part-Number. Google calls these extra numbers GTIN. If you are a merchant and you sell products where BRAND and Manufacturer-part-number info is normally available, you must include it. If you sell CUSTOM MADE or one-of-a-kind items where no manufacturer part number or brand even exists, then you must use the "identifier exists" field and mark it FALSE.