Carmen Rose wrote:My favorite material is good, old fashioned muslin. The thinner, the better. I stretch it over an old wood window frame and staple gun it in place, then prop the window (which I'd removed) over it in a sunny spot. It doesn't last forever but I don't wonder what might be leaching into my food out of a fiberglass or plastic-based window screen. It's cheap and easy to replace. Works really well and the window always fits the frame. Plus, it's biodegradeable and doesn't hurt the environment at all!