The Archaeology Grooved Photo Board comes with plastic characters and numbers that easily slide onto the black rubberised black panel. The panel measures 340x180mm (300x140mm inside the frame) and is made of washable rubberised grooveboard and anodised aluminium frame. WHITE characters (234) and numerals/symbols (264) (19mm). Like any specialist equipment - please take care of it, do not leave it soaking wet. Dry it out and clean it before storing.