Installing Insect Screens for Single Hung Windows with tracks is pretty straight forward.
First, insert the top of the window screen (the end with the springs) into the U-shaped track at the MIDDLE of the window.
Then, push up on the screen slightly to allow for the bottom of the screen to move behind the bottom lip directly under the U-shaped track. The springs installed at the top of the screen should then push the screen down and hold it in place.
Window Screen Resource Center
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