Window Heat Insulation Film is a durable PVC film designed to block cold drafts in winter and help keep cool air inside in summer when used with air conditioning. It resists deformation, tear, water, and chemical corrosion for long life and can be reused season after season. Key benefits - Improves winter warmth and summer cooling by reducing heat transfer through windows - Durable, tear and deformation resistant, waterproof, and chemical resistant - Long-lasting, reusable clear film Compatibility and features - Suitable for octagonal windows, window sills, floor-to-ceiling windows, parallel moving windows, and push-out windows - Package includes Window Heat Insulation Film (1) and Hook-and-Loop Tape (1) - Size options are W x H; the width of the hook-and-loop tape is 2 cm Size and installation guidance - Please measure accurately: our sizes are W x H - If sticking to the window frame, ensure each side of the frame is at least 5 cm long and the frame is smooth and flat - For frames inside the wall or with a narrow/no frame, add 4–5 cm to W and H and extend/fix it on the surrounding wall; the wall must be smooth and flat - Easy to install and remove: double-sided tape attaches the film to the window frame; ensure the frame surface is dry and clean before installation; at season end, simply remove Usage scenarios - Drafty winter windows: reduces cold air ingress and helps retain warmth - Summer cooling: helps keep interior cool while using air conditioning - Various window configurations: suitable for octagonal, floor-to-ceiling, and other window types, including push-out and parallel sliding designs Material and reuse - Thickened clear plastic film with good tenacity and cold resistance; tear resistant - Reusable year after year for ongoing insulation improvements