High Quality Liquid Chalk PensThe window pens glide smoothly over most Non-Porous surface, Wet erasble ink leaving even and smooth lines not as streaky as regular dry erase markers, making it easy to create clear and legible line every time, they are erasable, water-based, non-toxic, odorless, dustless, quick-drying, strong coverage, It is conforms strictly to ASTM D-4236 safety standards.
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