The Econo Table Frames were created to provide growers on a budget with a strong table frame that works with all of the accessories shown here. Constructed of strong galvanized 1" steel tubing and injection molded ABS plastic corners, the Econo Table Frames have strength to spare. They come in 1 and 2 tray sizes for up to 18 square feet of horizontal growing space, and are also available as an add-on to turn a 1-tray system into a 2-tray system. Picture shows tray (not included). From American Hydroponics.