These crayons draw smoothly as silk on almost any surface - including papers, glass, mirrors and whiteboard. Because they are water soluble with just a few strokes of a dampened paint brush drawings become beautiful watercolour paintings! Creations on any non-porous surface can be easily wiped away using a damp cloth making it great for window art - inside and out. All Kitpas crayons are non-toxic, eco-friendly and allergen free.Made in Japan.