GREAT QUALITY SCREEN! Tired of buying a window screen frame, window net screen, or window screen mesh that falls apart almost immediately? We have heard the cries for a better product and have delivered with Fenestrelle Expandable Window Screens! Our adjustable window screens are designed for double-hung windows and are even useful as a window screen replacement. ENJOY THE BREEZE! Fenestrelle Sliding Window Screens allow fresh air and gentle breezes in while keeping mosquitoes, bugs, and other insects out. Our window screens feature a white, powder-coated aluminum box frame and fiberglass screen that hold up to the harshest of conditions. Weatherstripping on the top and bottom adjust to rough surfaces. Faster and cheaper than fitting permanent window screens, our window screens give you a durable and attractive choice that also works great with cats! EASY TO INSTALL! Simply open your window and inset the Fenestrelle Window Screen. Expand it to fit the width of the window. Finally, close the window until it contacts the top of the screen. To change the orientation, find and remove the set screws from the frame channel. Slide the two screen panels apart and reinsert the guide pieces into the opposite frame channel. Close the screen, reinsert the set screws and you are good to go. MULTIPLE SIZES! Our Fenestrelle Window Screens comes in several different sizes to fit windows of all sized. Check out the Fenestrelle Brand Store to find a size that is perfect for you! Our medium window screens horizontal dimensions are 15" x 21" and expand to 40" wide. As an added feature, this screen can be converted to vertical orientation. The vertical dimensions are 21" x 15" and expands to 28" wide. If you wish to convert your screen, follow the instructions in our video.