I have 2 cat lids and one lid can fit small tin too , I always store our food in other containers so now will do it for Oreo's foodI think Amazon, and grocery stores sell plastic lids you can put on the pet food cans once they are open. In the grocery they will be hanging off the ends of the shelves in bags. here is an example from Amazon. They should work for other canned food, though I've heard it's not a good idea to leave open cans of tomatoes due to the acid in them. It's better to put tomatoes/tomato sauce in glass or plastic containers. I could be wrong about that.
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