An adjustable support riser for vertically stacking letter trays is disclosed, comprising a riser body (10) having a lower clothespin type attachment configuration (30, 32, 42) for securing to a lower letter tray, and an upper attachment socket (12) for attaching to a downwardly projecting (52) foot...http://www.google.com/patents/US5054629?utm_source=gb-gplus-sharePatent US5054629 - Adjustable tray riser
