(a) Dual use design for books & files. (b) Forms three wide sections after assembling. (c) Easy to assemble by sliding the plates. Instructions printed on the box. (d) Just fillip the back side down & reposition the front plate for choosing depth between books & files. (f) Indexing stickers on both front & back plate for writing nomenclature.. (g) Useful at offices to vertically compartmentalize cupboard shelves for neatly organizing & archiving records . (h)Quick way to organize files on office desks.