Drive Files to Dropbox is a file transfer, backup tool for Google Drive.which allows a user to save Google Drive's files to Dropbox folder directly.
One can backup files directly from Google Drive to Dropbox.
Advantages:
1.Its Super Fast
2.Integrates your Google Drive with Dropbox free.
3.It provides connect with Google Drive.
Note: You can save up to 100 files at a time.
Transfer them here
Another alternative is www.mover.io