There are two kinds of files which will work as a restart file. First are the restart.sph files created by the previous run. These files, produced by the CHKPT subroutine every NITCH iterations, are constantly rewritten to save memory while remaining up to date. More practical however, are the ``outxxx.sph'' files, where ``xxx'' is a 3-digit integer, produced by the DUOUT subroutine at code time intervals of DTOUT, and when a run terminates. To use these files, in the same exact format as the restart file above, simply rename the file ``restart.sph''.