-Saving, Waterproof Material: This window sealing kit is crafted from a waterproof fabric capable of reflecting intense sunlight, thereby helping to cool the indoor environment more . By minimizing the loss of cool air and blocking the intrusion of hot air, it effectively reduces consumption. Superior Sealing Performance: This portable AC window vent kit uses a drawstring cuff design, achieving a - seal. It locks in cool air while blocking hot air, rainwater, dust and insects to maintain a consistently comfortable indoor environment in summer. Tool-Free Easy Installation: No drilling or special tools required. Clean the window frame, apply the supplied sealing tape, attach the window seal, pass the exhaust hose through the round opening, then tighten the cord lock and secure with included straps. Allow 24 hours after installation before regular use.