What material is Window Clings made of?

Clear Window Clings are made of 8mil thick clear glossy material with a paper backer that will be peeled off prior to application. White Window Clings are made of 8mil thick white opaque glossy material with the same paper backer that will be peeled off prior to application. Both are suitable for indoor or outdoor use. Ideal for POP signage on glass or other very smooth, clean surfaces. Excessive heat or cold will not allow the product to cling to the surface.