These postcards are made with heavyweight 184lb (300gsm) paper that has a vellum drawing finish and is able to handle wet media applications. The front of the postcard is left blank for your art. The back is printed with traditional markings of a postcard so you can mail your piece and share your art. It's great for pen and ink, watercolor, gouache, acrylic, graphite, colored pencil, marker and collage!