TL:DR; AnyClient is a free platform independent file transfer application that supports all major file transfer protocols including FTP/S, SFTP and WebDAV/S.
Download AnyClient Freeware - Rating: 4.72
Secure and high performance FTP file sync product
FTP Voyager: secure FTP client with scheduler and sync. FTP, SFTP (SSH), FTPS and IPv6 support. "Scriptless" automation, drag-n-drop file movement, multiple transfer threads, folder synchronization, large file resume (checkpoint restart) and more!
Award-winning file transfer ftp software for secure and reliable file transfer over FTP, FTPS and SSH. FTP Commander Deluxe supports multithreading data transfer, file synchronization and 128-256 bit encryption.