MDO plywood offers a reliable material for making signs because of its moisture resistance and durability.  It is very popular with Real Estate Developers who want to showcase renderings or photos of their projects on site.  The material is very strong and when installed onto posts properly can withstand the elements.   Highway departments nationwide typically specify signs made from this plywood product. Because it's dimensionally reliable -- and free of knots and patches -- the inner core of MDO is dense and consistent, typically without significant defects. When the resin overlay is added, the material provides a slick and smooth surface ideal for paint and lettering. Routed letters, corners and edges remain clean and resist chipping and splintering.