EXTRA HEAVYWEIGHT PAPER: Stands up to advanced dry & wet media techniques. Great for working in heavier washes or overlaying washes (glazing) of watercolor or gouache. CRAFTED FOR MIXED MEDIA: Double-sized (from non-animal materials) for enhanced wet strength and glowing color. ERASABLE & TOUGH: Accepts multiple erasures of dry media and lifting of wet media. DURABLE: Thick board, premium U.S. coil binding, and heavy-duty art paper equals a sketchbook that is built for serious use. PREMIUM QUALITY: Exceptional features make Stillman & Birn the popular sketchbook choice, cherished by artists of all levels.