This is a set of 21 Manila folders (Manila files). Unlike the thick cardboard of individual folders made by domestic manufacturers, these are made of a thin, durable, and flexible material, making them ideal for filing. They are US letter size (29.5 cm wide: 21 cm long), which is almost the same size as A4. This is a set of 21 folders (left tab, center tab, right tab: 7 each).