Adjustable fit for window and interior units - Size and compatibility: adjustable cover designed for 21L x 15H x 3.5D inches. Fits most 5000-7000 BTU window type air conditioners and many interior-type unit sizes. Double insulation for energy efficiency - Windblock inner lining and outer cover are sewn together for easy setup. - Embedded cotton in the interior helps prevent warm air from escaping and cold air from entering the AC, reducing winter heat loss. Secure and easy to use - Dual strap fastening on both sides with adjustable straps and elastic cords around the cover for a secure, snug fit. - Snap closures on the two adjustable straps ensure the cover stays in place and is easy to put on and take off. Soft, durable material - Made from high-quality soft polyester fabric. - Washable and durable, with a clean white finish that blends with white home decor. Protection and cost savings - Eliminates the need to remove and reinstall the AC for seasonal use, helping to lower heating costs. - Protects the unit from dust and debris and helps keep the room warmer in winter by reducing drafts. Use scenarios - Winterization of a 5000-7000 BTU window unit or interior-type air conditioner in living rooms, bedrooms, or offices. - Off-season protection in apartments or rental properties to prevent dust and weather exposure. - Quick, tool-free installation and removal for seasonal storage or redeployment without disassembly.