sizeSystem constant
IRI for schema:sizeSystem [Expects: https://schema.org/SizeSystemEnumeration, https://schema.org/Text]
The size system used to identify a product's size. Typically either a standard (for example, "GS1" or "ISO-EN13402"), country code (for example "US" or "JP"), or a measuring system (for example "Metric" or "Imperial").
Can be used on: https://schema.org/SizeSpecification
Implementation
static const sizeSystem = IriTerm.prevalidated(
'https://schema.org/sizeSystem',
);