thevittfile

The plugin looks up the sub-attributes in your product, then for each value it looks up its parent and adds the parent attribute and the parent value in the product. 
When using a filter with the main attribute on the store page, all the products that have that main attribute are returned, which are the same products that contain the associated sub-attributes.
Important: 
You can’t create multiple hierarchy levels, just one. 
Two diferent attributes cannot contain the same sub-attribute.
<h3>Documentation</h3>
<a href="https://github.com/vittfiles/vitt-attribute-hierarchy" rel="nofollow ugc">vitt attribute hierarcht for woocommerce</a>

Vitt Attribute Hierarchy for WooCommerce

This plugin works simulating a hierarchy for attributes and subattributes.

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