3M - In-Line Book/Document Holder Document holder keeps documents between the monitor and keyboard to help reduce head, neck and eye movement. Design offers a versatile angle and height adjustment for easy viewing. 18" wide, transparent backplate supports wide and heavy documents. Elastic line-guide enables easy data entry and helps keep up to 300 sheets in place. Document holder includes a skid-free base and is made of 40 percent pre-consumer recycled material.