asin property
//en.wikipedia.org/wiki/Amazon_Standard_Identification_Number)'s article).
Note also that this is a definition for how to include ASINs in Schema.org data, and not a definition of ASINs in general - see documentation from Amazon for authoritative details. ASINs are most commonly encoded as text strings, but the asin property supports URL/URI as potential values too.
Implementation
String? asin;