Abstract: A combined speedometer and tachograph assembly has speedometer and tachograph indicia respectively arranged at one and the other side of a translucent plate and respectively adapted to be illuminated by separate light sources at opposite sides of said plate, the light transmission capability of the plate being such that the speedometer indicia when viewed from said one side of the plate are visible by the reflection from the indicia of artificial or natural light incident from said one side, but the tachograph indicia are only rendered clearly visible by the transmission through the plate of light incident on the tachograph indicia from an artificial light source at the other side of the plate.