- Energy-saving air conditioner window seal: blocks backflow of hot air, reducing room cooling load and lowering power use. An environmentally friendly, cost-effective solution that is easy to install and remove. - Durable material: high-quality waterproof polyester provides reliable windproof protection in all weather. - Easy, tool-free installation: no drilling or tools needed. Place the hose in the window frame, unzip, and tighten the seal for an airtight fit. - Year-round temperature control: keeps your room comfortable all year. When it’s cooler outside, you can leave it in place and simply open or close the window; reuse next summer. - Wide compatibility: fits most standard window openings and AC hoses; adjustable width and flexible seal accommodate common sizes. - Use scenarios: hot summer city apartment with a window unit; shared living spaces in rentals; small home office or workshop with a window AC.