Keep your important documents ready for reference with this heavy-duty binder. Metal round rings keep 8-1/2" x 11" pages and dividers organized and secure, and you can load the spine ID holder with an insert for easy identification. Spine-mounted rings lock so they won't gap. 3" ring capacity accommodates approximately 275 sheets. Slip loose documents into the two interior pockets. Each pocket holds up to 20 sheets. Binder also features polypropylene construction, a sturdy chipboard core and exposed rivets.