Symantec WINDOWS INSTALLER EDITOR 8.0 Reference page 217

Windows Installer Editor Reference
Compression Option
Select Uncompressed external files.
Share media destination/size info with previous media entry.
Mark this check box.
Include Features/Components section
Click Add and select the features and components to leave uncompressed.
14. Click OK.
After compile, the destination directory CD 1 contains the .CAB file and as many
uncompressed files as can fit on the CD. All remaining uncompressed files are in the
directory CD 2.
Organizing Your Installation Into Releases
217