In addition to narrative text, the following line formats may be used:
Conditional (C1)
This field contains additional information for which no other field has been defined within the message.
This field is to be used instead of field 72, only when that field is not sufficient.
The structured line format may be used for bilaterally agreed codes.
Any code must be between slashes and must appear at the beginning of a line.
Narrative text must not begin with a slash and, if used, must begin on a new line and be the last information in the field.