No tools required. Cheap and easy. I came up with a screen scheme that works for me and thought I would pass it along. Just cut your screen a little larger than the opening and secure with magnets. Go the extra for Neodymium Magnets.I have 60 of them. Seller is Magnet-House on Ebay. Fast delivery and good product. I used N50. The higher the N the stronger the magnet.

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