Hobonichi Graph Notebook - A6 SizeNotebook Details This graph paper notebook is made with Tomoe River paper, opens completely flat, and the printing comes in four different colors across the book. This notebook has 240 pages and uses the same 3. 7mm graph paper as the A6 Hobonichi Techo. The Tomoe River paper is the same thin, durable paper as that used in the Hobonichi Techo. This allows the 240 page book to stay at a mere 8mm thick, giving you plenty of room to fill to your hearts