The range of porthole instruments are mounted onto mahogany-coloured wooden boards with brass corners. They feature white faces with black hands and roman numerals, and 12cm cases which have been treated with a special tarnish free coating so that they do not require polishing. Quartz clock movements use 1x AA battery (not supplied). Barometers display pressure in millibars and inches. The boards offer provision to hang in either vertical or horizontal format but would require careful repositioning of instruments to do so. Board measures 33x18cm.