Ultimately this is pretty easy. Not too many variations.
“please fabricate u/l fixed expander with buccal tubes”
or
“please fabricate u/l fixed expander”
This is pretty standard for fixed if you want to archive the script for future patients.
Only variation would be one of the following:
1. Please solder anterior bite plate
2. Please solder facemask hooks
3. Please solder tongue/thumb crib