Acid free.A Scrapbook with a twist.The Flop Book has an amazing secret - it has a drop down section for little surprises, etc, hence the name Flop Book. 4 of its pages are 5inchs x 5 inchs with additional pages in triangles. It can be used as a mini scrapbook or even as an amazing card.The plastic wallet can also be decorated! Use stitching, alcohol inks, papers, paints, rubons, just about anything you like.Also the other two designs in this range available here at Ginger Pickles.