Thing > Property > additionalProperty

A property-value pair representing an additional characteristics of the entitity, e.g. a product feature or another characteristic for which there is no matching property in schema.org.

Note: Publishers should be aware that applications designed to use specific schema.org properties (e.g. http://schema.org/width, http://schema.org/color, http://schema.org/gtin13, ...) will typically expect such data to be provided using those properties, rather than using the generic property/value mechanism.

Usage: Fewer than 10 domains
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Values expected to be one of these types
PropertyValue
Used on these types
Place
Product
QualitativeValue
QuantitativeValue

Schema Version 1.999999