The Langton watercolour paper is colour stable, mould made & acid free. The `NOT` surface is most popular, particularly for watercolour & line & wash work. (It can also be used for pastels, inks, designers` gouache & acrylics.) The `ROUGH` surface, which is moderate, is recognised as ideal for loose impressionistic work & often preferred for landscapes & seascapes. 12 sheet block. 14x 10. 140lb/300gsm.