The inventive concept is a device which is used to secure a sheath or stack of papers contained in an architectural sheet rack clamp. The device is essentially a three-tiered rectangular structure forming two parallel, length-wise channels within the spaces defined by the three tiers. One channel, situated as the upper clamp retaining channel, is structured so as to securely accommodate the typical sheet clamp used to store such materials as architectural drawings, maps, and other similar over-sized sheets. The second, or lower desk anchoring, channel of the device, contains two adjustable fastening means, enabling attachment of the lower desk anchoring channel to a desk, draftsman's stand, or table.