SUFFIX

The SUFFIX system initialization parameter specifies the last two characters of the name of this system initialization table.

SUFFIX=xx: The first 6 characters of the name of the SIT are fixed as DFHSIT. You can specify the last two characters of the name, using the SUFFIX parameter. Because the SIT does not have a TYPE=INITIAL macro statement like other CICS® resource control tables, you specify its SUFFIX on the TYPE=CSECT macro statement.
The suffix allows you to have more than one version of the SIT. Any one or two characters (other than NO and DY) are valid. You select the version of the table to be loaded into the system during system initialization by coding SIT=xx in the PARM parameter or the SYSIN data set. (You can, in some circumstances, specify the SIT using the system console, but this is not recommended.)

Restriction: You can specify the SUFFIX parameter in the SIT only.