1. Blocks hot air from entering: The window seal kit prevents warm air from flowing back into your room, helping to keep the space cooler. Our waterproof window seal keeps unwanted guests and rain out while creating a 'closed environment' that maintains a cooler room for longer. 2. design: A great upgrade for our window seal. Unlike other zipper seals, our product features an adjustable coupling that ensures better sealing and reduces air convection. Save electricity during hot summers and cut down on costs significantly. 3. Universal: The AC exhaust hose seal is compatible with all portable air conditioners and tumble dryers. It fits all types of windows—whether they open to the left, right, tilt, or are skylights (excluding sliding windows or doors)—as long as the maximum circumference does not exceed 2m/3m. The windows remain fully functional and can be opened and closed as usual. 4. Reusable: The window seal for portable air conditioners is made of highquality, durable, waterproof, and washable material. It's lightweight and easy to store. When not in use, the seal can be easily removed and reused the following summer.