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Main Image - the image your potential Buyers will see in the top left of your eBay Item and next to the Items' title in the Search results.
Default Image URL - if Magento Product does not have the Main Image, this image will be shown instead. You should use only absolute URL in this option e.g. http://mymagentostore.com/images/defaultimage.jpg
Super Size - allows you to provide larger images (up to 800w x 800h pixels - 800 pixels on the longest side).
Gallery Images - adds small thumbnails that appear under the Base Image. You can add up to 11 23 additional photos to each Item on eBay.
Change Images for Attributes (applied only to Configurable Products) – allows selecting Magento attribute by which the Multi-Variational Product images will be switching on eBay.
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