sealing performance: minimizes air gaps to cut energy costs and keep a steady indoor temperature across seasons. Broad compatibility: designed for casement and roof windows, suitable for a range of window installations in home or workplace settings. Easy peelandstick install: quick, tool application you can do yourself to seal around a window air conditioner or other openings. Deformation resistant material: density sponge stays stable and maintains effective sealing despite temperature changes. What you gain: reduces drafts around window units, boosts comfort, and supports more efficient heating and cooling. Materials and fit: density sponge provides reliable sealing for typical gap profiles between sash and frame. Use scenarios: Sealing around a window air conditioner in a living room to stop cold drafts and improve AC efficiency. Upgrading casement windows in an office to reduce summer heat gain and winter heat loss without bulky weatherstripping. Sealing roof or skylight windows in a workshop or attic to minimize temperature swings and lower energy use.