This 9x12 inch Hahnemuhle Harmony Watercolor Block contains 12 sheets of 140 lb rough surfaced watercolor paper. Produced with high quality resources and pure spring water, this acid free, light fast block is specifically designed for use with all wet media application including watercolor, gouache and more. Hahnemuhle Expression blocks feature 100% vegan surface sizing that allows colors to stand out distinctly on the paper and impress with a natural brilliance while preventing blurring and smudging of your work. Masking tape can be used & removed residue-free.