the “Heavy Duty” Edition. Each pack contains a pair of memo-sized Work Books, durable enough for your toughest assignments. The covers are made of extra-beefy “Super Duty Chipboard” and have been screen-printed with thick, opaque ink, one in DDC Orange and one in Blue Sky Blue. The “flip” books are bound from the top with sturdy Double-O Wiring, to make it easy to take notes with one hand while holding the book with the other. Each book contains 80 pages, Ruled on the front with a Double Graph Grid on the back, so you’ll have space for making lists and for sketching out plans too.