Flatbed printers are useful when you need to print on a surface that is rigid, flat or uneven. The way that a flatbed printer works is that the media to be printed on is placed on a flat bed and is locked into place, sometime using a vacuum, to ensure that it does not move during the printing process. The printing head is generally moved over the surface to be printed on. In some cases the printing head is follows by a UV light to dry the print almost instantly. Spot colors such as white and varnish are allowed with flatbed printers since they tend to be subtractive. Flat bed printers also allow for the use of inks that can add dimensionality to the print. Please ensure to read all the instructions that come with your printer to ensure that you are purchasing the proper supplies for it as well as to ensure that you are using it correctly.