CONCAT (Concatenate) keyword

You can use this field-level keyword to combine two or more fields from the physical-file record format into one field in the logical-file record format you are defining. The name of this concatenated field must appear in positions 19 through 28.

The format of the keyword is:

CONCAT(field-1 field-2...)

http://publib.boulder.ibm.com/infocenter/iseries/v7r1m0/index.jsp?topic=%2Frzakb%2Frzakbmsttdjdups.htm