firstly please dont type in capitals as it's very annoying to read!
ok now to your problem,the par files are parity files which are not for winrar but smartpar.
par files are really quite clever as they can make up missing portions of a split rar file but only if you have enough par files to cover the amount of rar files you are missing!
a nice tutorial and a download of smartpar can be found at
http://www.slyck.com/smartpar.php