Strathmore 500 series 100% cotton bristol is an industry standard. Plate Surface has an ultra-smooth finish thatis unsurpassed for detail work using traditional pen and ink tools, specialty pens, specialty markers and airbrush. Vellum Surface has a toothy finish that is excellent for graphite pencil, colored pencil, sketching sticks and specialty pens and markers. It is also is very good for charcoal, pen and ink, airbrush and light washes. Not recommended for traditional watercolor techniques.