INCREASES COOLING PERFORMANCE - Enjoy a cooler environment in the summer thanks to! Our product seals the edges of your window even when it is open. It encircles your air conditioner's vent duct and blocks hot air return, allowing your mobile air conditioning unit to be more efficient and cool your room faster. INCREASES COOLING PERFORMANCE - Enjoy a cooler environment in summerthanks to! Our product seals the edges of your window even when it is open. It encircles your air conditioner's vent duct and blocks hot air return, allowing your portable air conditioning unit to be more efficient and cool your room faster. REDUCES ENERGY CONSUMPTION love the Earth! This window seal helps to reduce energy consumption and carbon dioxide emissions, which is particularly important in the summer due to the heavy use of air conditioners. By preventing hot air from circulating in your room, the window seal allows you to save money on your electricity bills! EASY INSTALLATION - NO DRILL. Everything you need comes with your Window Seal! Simply apply the tape to the inside of the window frame as well as to the window. Attach the caulking fabric to the tape. Then, unzip and place your air conditioner hose outside the window. Finally, close and tighten the zipper around the pipe. It's that simple. UNIVERSAL- Suitable for all portable air conditioners and clothes dryers, regardless of manufacturer. Whether it is windows that open to the left or to the right, tilting windows or skylights, the window seal will do the trick. This product is suitable for windows with a maximum perimeter of 500 .