Abstract: An elongated tubular body is provided for reception within the confines of closed rings of a "ring binder" and with the body spaced radially inwardly from the inner surfaces of the rings sufficient to enable sheets of paper slidingly engaged with the rings to slide thereabout without interference with the tubular body. The tubular body includes a first side opposing the base of the "ring binder" ring assembly from which the rings are mounted and the body first side is stationarily secured to the base. A second side of the body remote from the first side has a saddle cut opening formed therein and a thin wall cover closely overlies the second s de closing the opening and is guidingly mounted from the body for shifting relative thereto between positions opening and closing the opening.