ColleenT,
If you are getting the thing I think you ordered it is actually real cork bark that has been glues to a manufactured cork backing. I used the same think in my Mantella and Red Eye tanks. Just a heads up. All of the ones we got had a sort of natural arch to them so they didn't sit flat. I took some silicone and smeared it all over the glass and then laid the panel on the glass and weighted it down so it layer flat. I let it sit like that for for 24 hours. This not only flattened it out, but ensures Flies, Crickets, or frogs can not get in behind it.
Can't wait to see how this turns out!