External films are are of weather resistant construction having additional UV barriers to help protect the film from degrading through exposure to sunshine, and also having a strong waterproof adhesive. They are particularly used when inside access is not always possible or depending on the type of glass, in particular laminated, Georgian-wired, heavy tinted glass or some double or tripled glazing.

Opalux® Reflective Grey/Silver Privacy Mirror film offers superior one-way privacy effects than conventional reflective solar control films, and is of particular use in combating severe solar heat gains and glare problems. The external product is the best performing product for the heat and glare rejection as it reflects the light rays before it passes through the glass.

They also help to alleviate the discomfort caused by excessive heat and by glaring reflections off computer screens, assisting in compliance with the Workplace (Health, Safety and Welfare) Regulations.

The films are applied externally and, in daytime, lend the glass a silver reflective outside appearance, whilst from the inside, the visual effect, much less noticeable, is a light tint.