Sitaram Spiral bound Sketch book has high quality thick paper of 140 GSM. This drawing book has Super White cartridge paper which makes it perfect for professional drawing. Sitaram Sketch Book comes in 3 sizes A5, A4 and A3. Super White Cartridge Sheet 140gsm is used in all sketch books Features : Perfect for use with Pencil, Chalk, Graphite, Crayon, Charcoal Made from high quality Cartridge paper 140 gsm Due to its compact size, A5 sketchbook can be carried anywhere for beautiful drawing experience and it has 50 sheets as compared to A4 and A3 having 25 sheets each.