I made a frame and stapled wire netting to it, when the door is open it just fits in the opening. Our cat used to come and go through a bead curtain over the kitchen door so I would not be convinced that it would be a preventative, it would also restrict air movement which is why the door is open in the first place is it not?

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Digger-07

"If you think you can, or think you can't, you're right" Henry Ford.