Battery pad that inhibits corrosion on the tray

Have any of you heard of a hard cardboard material that sits under the battery and inhibits corrosion on the tray? I remember coming across this type of material on the job when installing stand-by CAT generators, but can't remember the name of company they came from or the name of the item. I've searched the web but haven't come up with anything.

It's a reddish color and I assumed it was for corrosive protection.
Thanks