... . For removal protection. For copper foils. Aluminium plate, etc. Index Color: transparent, milky white, blue, white outside & black inside Specification ... tolerance: ±0.004mm,Length tolerance: ±3%Appearance: smooth, even color, no crease, no air bubble, no stain, good purity, ... no deformation. AppearanceSmooth, even color, no crease, no air bubble, no stain, good purity, ...