Vertical Communications DSU and DSU II - Manual (Page 37)

7. Press TRANSFER/CONFERENCE to program a name. Enter
digits from the Letter Code Table on page 2-9 to spell name (up
to 16 characters allowed),
—OR—
— Press TRANSFER/CONFERENCE to leave name blank.
8. Press TRANSFER/CONFERENCE to save the number and
name.
9. Repeat above steps (beginning with choice of storage location) to
store all speed dial numbers.
10. Press SPEAKER to end.
GCA70–245 Programming The Attendant Features
LCD Speakerphone Reference Manual 2–17