Window Mask is the best way to protect windows during interior and exterior plastering, paint oversprays, mortar stains and from some acids. It is a strong, low density 2 mil polyethylene film, coated with a solvent based low tack adhesive. Adheres to substrates such as plastics, finished metal and aluminum without any damaging effect upon removal. Removal is fast and easy. 30-Day maximum application time. Color: clear.