HTTP/S - Feeds will be downloaded from an HTTP or HTTPS endpoint you provide. Basic authentication is supported.
FTP/S - Feeds will be downloaded from your FTP or FTPS server. We support username/passwords authentication, relative directory route, and non-default ports.
Google Merchant Center - If you already have a full integration to the GMC, and depending on a the size of your inventory, it may be possible for us to pull your product data directly from the GMC using the Google Shopping API. To check the availability of this option for your account please contact you Stucco account manager.