Rat-Entry Hole in a House in Gainesville, Georgia

I will say this much: At least the air-conditioning installer tried to seal up this hole, which is more than most of them do. Unfortunately, I have no idea what that stuff they used is. It looks like it could be spackling or drywall compound, but I'm not sure.

What I am sure about is that it didn't keep the rats out of the house; so whatever stuff it was, it wasn't the right stuff.
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