This is a brand new rich result designed to better support product variant scenarios for ecommerce sites. They also added a new isVariantOf property to the product structured data documentation and clarified that Google support product variants with distinct URLs. The purpose of this update is to enhance the support offered to e-commerce websites in managing product variants.
Recognizing the complexity and significance of product variants for e-commerce, particularly in categories such as apparel and electronics, Google is providing expanded examples and guidance on implementation of product variant structured data.
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