Winston & Newton's watercolor paper pads offer optimal results for watercolor painting. Standard paper wrinkles when it gets wet. This phenomenon is known as cockling. Even when the paper has dried, it will never lie completely smooth and flat again. While you'll pay more for watercolor paper, the results are well worth the extra money.
W&N water color pads boast thick, heavy paper with a special surface that has grain in it. 190gsm 90 lb paper is fine for most purposes, but it doesn't get the job done for watercolor work. The thicker, heavier surface lets you paint freely without worrying about wrinkling. You can use the watercolor pad on a a table, on a wooden board that allows you to tilt it toward you, or with a watercolor paper block. The pad measures 12 x 16 inches and has 10 sheets of 140 lb paper.