[Keep Warm in Winter] A window insulation kit used in winter to keep wind/cold out and prevent heat loss. Made of thickened environmentally friendly PE material, tear-resistant, waterproof, high transparency, good airtightness, non-defrmation, long-term use. [Save Your Electricity Bill] In winter, the windproof window film will keep your room warm and insulate it from heat. In summer, prevent heat from entering your room. Reduce your electricity bill. Meanwhile, our secondary glazing kit is dustproof, windproof and soundproof. [DIY Installation Window Sealing Film] Measure the outside of the window frame, recommend adding 10cm to order the size of the window insulation kit. No complicated installation steps. You just need to prepare scissors and a ruler, follow the installation picture, install and remove at at any time. [Wide range of applications] Our interior window sealing kits are suitable for casement/outward opening windows. Aluminum alloy and plastic steel window frame are the