Google Base: How to use the "product_type" attribute

[Kristijntje]

If your product doesn't fit with the exact values on the example product_type page, you can include some variations; the most important thing is that the product_type be relevant and that it distinguish between an actual product and the accessory for the product. For example, for the above keyboard example, the product type "usb keyboard" is also acceptable. If you're selling Ipod skins, the values "accessories" or "mp3 accessories" are fine.

Finally, some providers are including values such as "health, beauty, fragrances" or "MP3 Players > Ipod > Ipod Accessories > Ipod Skins" as their product_type values. Since we only accept one value, neither example works. Unfortunately, entering your values with commas or > symbols will miscategorize your products, and searchers won't be able to find them. So make sure you're using correctly formatted, relevant values when using the product_type attribute.

full article: http://googlebase.blogspot.com/2007/04/h...ibute.html