Q-Connect Paper on Board Ring Binders. High quality 2 ring binders. Features include spine label for easy identification and indexing and a ring mechanism that opens and closes easily. A4. Capacity 25mm. Colour – Green.These handy, durable ring binders feature a standard 2 O-ring mechanism with a 25mm capacity for filing A4 documents. The ring binders also feature durable paper over board covers and spine label for quick identification of contents. Ideal for colour coordinated filing, this pack contains 10 green ring binders.