The VLT is the total visible light which passes through a window/window film. It is measured by percentage. The film gets darker the lower the percentage. (i.e. 90% VLT window film is virtually clear, while a 10% VTL is quite dark.) Depending on the manufacturer, the darker the film, the more heat is rejected. All solar window film blocks 99% UV rays.
← VLT (Visible Light Transmission)