Have you ever named a file with FINAL? Then FINAL2, and FINAL3? Is it ever really final?
This naming convention appears uncertain and negates trust.
Consider other options. Name the file with a date and time. Or, name the file with a version indicator like V1, V2, etc. If you save each revision in the same folder, you can easily find the latest.
Either way is easily identifiable, and looks much more intentional and professional when you send it to the recipient.