M2E Pro Listings do two things:
allow you to define which products in your Magento catalog you want to list on eBay.
allow you to define which eBay settings to use when listing products.
Products can be added to an M2E Pro Listing manually. Or you can define attributes that should be matched so that products are added automatically. For example, you can choose to add products automatically to your M2E Pro Listing whenever new products are added to a certain category in your Magento catalog.
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