Transform your space with the FND4F Window Frame from Keepshape Appliances & Renewable Energy! Our premium-quality steel frame is engineered for top-hung windows in both residential and commercial buildings, ensuring unbeatable performance. Featuring F7 energy efficiency and ND4F soundproofing technology, this frame excels in thermal insulation and noise reduction, offering you a serene and comfortable environment. Finished in grey oxide and built from galvanized steel, it promises long-term durability and style. Choose Keepshape for quality and innovation you can trust!