The 65mm capacity (90mm spine width) 4D-ring binder is truly a jumbo binder. I've inserted plastic pockets to hold A4 sheets and cuttings, so this whole assembly becomes quite heavy. Tabbed (extra-wide) subject dividers (not supplied) do not protrude beyond the edges of the sturdy plastic-covered boards. When full to capacity, turning over a big section of leaves, or going right to the far end is not a quick process, but secure if done carefully. If creating a large project, consider whether you go for a single very wide binder, or maybe two narrower ones. There are customisable front, spine and back pockets to insert your own cover sheets and titles, although slipping them in - best with the binder folded out - can be a bit tricky, especially with thin paper, so light card would be easier to insert. The height is approx 32cm, so check if it will fit into your bookshelf. Width 30cm; spine 9cm.