... factory.Artwork FormatPDF,AI,CDR,JPGMaterialArt Paper, Craft Paper, Coated Paper, Glossy Paper, Bible paper, Matte Paper, Offset Paper, Fancy Paper, Newsprint Paper, Woodfree Paper, Greaseproof Paper, Paperboard, Cardboard, Millboard, Corrugated Board ... than the book block spine, the more obvious the more sheets. Thus, square spine hardcover book not too thick, generally applicable ...