Notes about the UNS file extension:
To open this file type, a required software must be installed. Without it you only see a Windows message "The following file cannot be opened
" (Windows 7) or "How do you want to open this file?
" (Windows 10) if you double-click the file. There click on "More apps"
and choose a suitable software to view such files on your PC or from email attachments.
The UNS file type is primarily associated with 'Visual Navigation Suite' by Jeppesen Marine, Inc.. Visual Navigation Suite is navigation software. This was the extension used on older versions. The new versions use the .VUI extension.