1.New Custom hard cover conference folder 2.Ring Shape:O-Rings ,D-Rings 3.Thickness: ... book; children book, catalog, magazine, paper bag, paper box, calendar, folder, envelope, paper card, poster etc. 3. Free stock ... / 2 mm/2.5mm/3mm8. Cover: art paper, 128g and so on, with laminating & printing9. Inner ... : offset paper, 100g and so on10. Mechanism including: 2- ...