FEP (perfluoroethylene propylene) is the ideal choice for coating sight glass plates in chemical plants where maximum transparency and chemical resistance are crucial. As a fully fluorinated high-performance plastic, FEP combines excellent optical properties with extraordinary resistance to aggressive media. This combination makes it perfectly suitable for process observation under extreme conditions. FEP-coated sight glasses remain permanently clear and free from discoloration – even when in contact with highly corrosive or oxidizing substances. Thanks to its smooth, non-stick surface, FEP reduces deposits and allows for easy cleaning. Its resistance with sight glass plates to temperatures up to +120 °C, as well as its excellent electrical insulation properties, provide added safety in sensitive environments. Through its high transparency at a low refractive index, FEP allows for distortion-free visual control in reactors, pipelines, and analytical devices. It therefore significantly contributes to plant availability and process safety. Thus, FEP is not only a technical solution but also an essential contribution to efficiency and operational safety in chemical process engineering.