Pro Art Premier Hardcover Watercolor Field Book 9"x 12" 140# Wirebound 24sht- Features sturdy black-leatherette cover that keeps artwork intact while providing a firm handheld drawing surface. Acid-free white cold pressed paper is suitable for all wet media. 140lb/300gsm sheets are professional grade. Spine is double wirebound with thick gauge coated wires for effortless 360 degree page turning. Paper is sourced from certified sustainable forests.