OO/HO Gauge. 20x Short Wooden Ladders. 20mm X 8mm Train, Railway Scenery Made from a high quality MDF (medite) 2mm thick. Each ladders measures 20mm x 8mm. This listing is for 20 ladders I regularly make custom orders. Please contact me for more details. Made from high quality 2.0mm thick Medite (laser quality MDF), plain finish ready to be painted and decorated. These item are laser cut, the laser cutting process produces a brown finish to the edges of the MDF. All laser processing marks can be easily removed by a light sanding or simply painting over.