These Hahnemuhle Watercolor Cards feature high quality, 230gsm, rough surfaced watercolor paper. 30 cards measuring approximately 4×5.75 inches come enclosed in a stylish metal tin, allowing you to safely transport your artwork wherever you go. The round edge post cards contain an address field printed on the back for you to send personalized postcards to all your friends and family. Suitable for both wet and dry painting techniques the Hahnemuhle Watercolor Cards are perfect for watercolor, plein air painting, and urban sketch artists.