{"@context":"https://schema.org","@type":"Property","@id":"https://schema.org/addOn","rdfs:label":"addOn","rdfs:comment":"An additional offer that can only be obtained in combination with the first base offer (e.g. supplements and extensions that are available for a surcharge).","schema:domainIncludes":[{"@id":"https://schema.org/Offer"}],"schema:rangeIncludes":[{"@id":"https://schema.org/Offer"}]}