Special compact bases on the Traffic lights keep them upright even on the windiest of days, and safe and sturdy fittings abound ensuring these signs will last and last and last. The effect of the lights on the traffic lights is created by using coloured balls, painted black on one side. As they are rotated, using special turning rods, the balls give the effect of the lights changing. H.1100mm ALSO AVAILABLE: In sets or individually.