Kokuyo's ReEDEN notebooks are made with withered "yoshi" reed plants, harvested from Japan's Lake Biwa and Yodo River. The plants are then turned into pulp and produced into notebook papers. By harvesting the withered yoshi plants, they are prevented from rotting and polluting the rivers, hence maintaining healthy plant growth which is essential for birds and fishes, and also helps to keep the air and water clean. Kokuyo has developed a special cover for the newest range of ReEDEN notebooks which allows you to decorate the cover with any water-based pen. 30 pages of 6.5mm width ruled lines.