WB GTX

I am looking at getting a new track or buying one from a buddy. I have a 2000 Polaris 600 XCSP and he has a 2000 Ski-Doo MXZ 600. Are their tracks compatable? What does it mean on the track for windows, all open and 2 open, 1 closed? Isn't that where the drive wheel drives the track? How can there be closed windows? I don't have my sled here so I can look at the existing but it seems weird that you can have closed windows. I see it on the more aggressive tracks 1.25" plus.

ARANF7

THAT SKIDOO TRACK WILL FIT ON YOUR POLARIS WITH NO PROBLEMS, THE ONLY DIFFERENCE IS THE 3RD WINDOW CLOSED WHICH WONT AFFECT ANYTHING. ALL THE NEWER 600 POLARIS'S HAVE THESE TRACKS.