Payment Medium Format Supplement
This is the key that facilitates the commercial description of data for the selected payment medium format. This is printed in the coding line of the payment medium or copied into the appropriate field with data medium exchange, for example.
Thus, with debit memos, we can distinguish between collection procedure and direct debiting procedure.
You only use the payment medium format supplement if there is provision for this in the format specification.
In Germany, the payment medium format supplement is called Text key (Textschlüssel).