Upgrade your window insulation with this storm window plastic frame featuring a protective lip. Designed for both interior and exterior storm panels, it offers a secure, weather-resistant fit and supports 3mm glazing for improved energy efficiency. Simple to install and made for durability, it’s ideal for DIYers and professionals replacing old frames or building new ones. Each piece is cut to size, with detailed instructions encouraged at checkout. Note: All orders are non-returnable due to custom cutting.