Pentel Colour Brush Pens Colour - Brown - Medium Round Tip - 1.2 cm long; Valve-activated for smooth flow, without leaking; Refills available separately. Water-based and brightly colored dye ink flows easily, dries quickly, and produces transparent watercolor effects; Transparent Ink is great for wet on wet technique; Ink is not lightfast. Durable Nylon Brush Tip which retains its shape; Ideal for Manga, Illustration, Writing, Lettering & Drawing. Lighten colours by touching the tip of the pen to water; Create gradations in colour by touching brush tips with each other. Comes with a red protector which needs to be removed before using for the 1^st time; Difference in pressure applied while squeezing the ink cartridge will result in variations in ink flow