Arches Watercolour Paper 100% Cotton 300GSM Cold Pressed 20 Sheets - 4 Side Glued Block Arches Watercolour Papers are made from 100% cotton linters and is gelatin sized both internally and externally. Arches Aquarelle watercolour paper is one of the world's finest art papers because it is acid-free, pH-neutral, and air-dried. Watercolor paper blocks are glued on all four sides, which eliminates the need to wet and stretch the paper before painting because the glue keeps the sheet from curling and buckling during the painting process. Arches Aquarelle Watercolor Paper Blocks come in three surface finishes, two paper weights, and all in Natural White. Arches Watercolour Block is ideal for watercolour painting, ink drawing, and wash. Ideal for plein aire artists looking for a portable painting surface!