We're the second owners of our Windsport. When we bought the rig, it had a fiberglass screen with velcro attachment; appearing to be a user-addition just as Pete described. We added a "cut to length" piece of 1/2 x 2" wood that makes a perfect brace between the glass frame and window frame to safely prop it open. That comes in really handy for air circulation, and enjoying the night air and sounds in the spring and fall.
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