Anyone know what kind of plastic Ding All cover sheets are?

I’ve searched and searched the web looking for a similar type of plastic to the cover sheets that are included with most Ding All kits with no luck.  There are so many different types of plastic and technical terms that I don’t really know where to start.  I need the same thing in a 2’x4’ sheet.  Anybody know what those cover sheets are exactly (the clear square ones) or possibly where to find them?  Thanks!

Nevermind, I just found it…Mylar

I just saw this and was thinking Mylar also

I think any clear plastic works

I used some that I cut offf a 3 ring binder,,, worked good and it wasnt Mylar