id
- Unique ID of product. This field must be constant in your feed.affiliate link
– Link to product with your affiliate parameter.is in stock
– Supported values: "1", "true", "on" and "yes", "0", "false", "off", "no".availability
- Supported values: "in stock", "out of stock".direct link
– Direct URL on original product page without redirects and affiliate parameters.gtin
- EAN 13-digit number like 3001234567892.