Control-click the selected backup and select Show in Finder from the drop-down menu. In this case, go to iTunes > Preferences > Devices.
The mechanism is a bit different if you're searching for a specific backup. Here's how you find a list of iOS backups if you use iTunes:
If you follow these, nothing could go wrong. We've prepared detailed instructions on how to locate and move iPhone backup to an external drive both ways. There are two Apple ways to backup iOS devices to Mac - using iTunes or iCloud.
