product image sizes (Yes, I used regenerate thumbnails plugin)

Hi – I was wondering if there was a way to make the product sizes any larger in the store? I am using the plugin for an affiliate store (Tee Pimp) and have already changed the default image sizes and used the regenerate thumbnails plugin, however the images are still not the size I want them to be.
As they are t-shirts, I would prefer that they can be better seen.

Thanks,
Dave

https://wordpress.org/plugins/woocommerce/