Woocmmerce – Product image – Change from Thumbnail to Medium

I’ll try to explain clearly… I have 3000 plus products loaded into woo commerce/enfold. Each product was entered with a large image and multiple smaller images were generated by the system. 150×150, 300×300, 500×500 etc. These sizes also correspond the the Settings/Media/Media Settings within WordPress.

On the woo commerce Shop Page and the Related Products area of pages, the ‘thumbnail’ (150×150) image is pulled in for every product. When the site is set to 2-columns the images get stretched and become very pixelated. I would prefer not to re-upload all 3000+ product images and resize the thumbnails larger. I’m hoping, using css or a function, that we can link to the ‘medium’ (300×300) image instead of the ‘thumbnail’ sized image.

This might be a common request, but I couldn’t find anything like it on the forums or through other sites. Can you send over the function or css to make this happen?

Enfold… best theme ever!