What's the difference between firmware names SPC and SPH?

  Hello,

I has a swith model S5720S-52X-SI-AC and i try understand firmware name. Now the installed version is "s5720si-v200r008c00spc500.cc" and when I searched a new version i finded these options:

(see image attached)

<HUAWEI>dir
Directory of flash:/

  Idx  Attr     Size(Byte)  Date        Time       FileName
    0  drw-              -  Nov 29 2016 03:13:09   dhcp
    1  drw-              -  Nov 29 2016 03:12:38   user
    2  -rw-             36  Nov 29 2016 03:14:36   $_patchstate_reboot
    3  -rw-        290,944  Jul 14 2016 11:46:58   s5720si-v200r008sph005.pat
    4  -rw-          3,684  Nov 29 2016 03:14:36   $_patch_history
    5  drw-              -  Nov 29 2016 03:13:21   logfile
    6  -rw-            836  Mar 25 2017 00:36:25   rr.bak
    7  -rw-            836  Mar 25 2017 00:36:25   rr.dat
    8  -rw-             28  Mar 25 2017 00:36:12   private-data.txt
    9  drw-              -  Nov 29 2016 03:13:08   localuser
   10  -rw-      2,156,027  Mar 25 2017 00:36:58   help.web
   11  -rw-     64,524,572  Jul 14 2016 11:44:12   s5720si-v200r008c00spc500.cc

What's de difference between SPC and SPH?