product-type Type of Product

Category of product described in the element (for example, “book”, “software”, “article”, “issue”, “website”, “film”, “hardware”).
OPTIONAL on element: <product>
Value Meaning
Text, numbers, or special characters The type of product being reviewed, for example, “website” or “videogame”.
Restriction @product-type is an optional attribute; there is no default.
Tagged Sample

Indicating a book is being reviewed

...
<product product-type="book">...
 <publisher-name>Wildside Books</publisher-name>, Rockville,
 MD, 2010, Price: <price currency="USD">$4.99</price>. ISBN:
 <isbn>1557426805</isbn>, <size units="pages">330</size> p.
 (paperback)</product>
...