Lorell Aluminium Hanging Clamps, 18-Inch, Set of 6 Each clamp opens up to 1" and holds up to 100 sheets or 20 lb Clamps are made of extruded aluminum and include a clear plastic label holder for easy identification of your documents Hanging clamps are designed for use with drop/lift wall racks and mobile stands for drafting and engineering documents Each clamp opens up to 1-inch and holds up to 100 sheets or 20 lb. Clamps are made of extruded aluminum and include a clear plastic label holder for easy identification of your documents Hanging clamps are designed for use with drop/lift wall racks and mobile stands for drafting and engineering documents Each clamp opens up to 1" and holds up to 100 sheets or 20 lb.