Avery ColorStak products are high quality self-stacking desk accessories. These bright, angular trays fit neatly on top of each other, meaning that you can save space on your desk. Without buying separate risers, you can build up as many trays as you need. How will you stack yours? These Letter Trays come as a set of 2 green trays (with blue, pink and black trays available separately). You can stack them traditionally - one on top of the other, but they will also stack at 90 degrees and front to back. Choose the arrangement that best suits your needs. Avery ColorStak Trays are made from strong ABS (Acrylonitrile Butadiene Styrene). This makes them hard and rigid with excellent impact resistant. Each tray has a shiny gloss finish that is scratch-resistant, so they will always look smart on your desk. ColorStak is available in 4 colours, which have been chosen to complement each other. Mix and match your trays as you stack to make eye-catching combinations. ColorStak Trays have been designed to hold A4 and foolscap documents, folders and brochures. Also available: Avery ColorStak Accessory Trays for notebooks, pens, and smaller documents. Fits on top of the ColorStak Letter Tray.