Traffic-light signalling and operation to a double red light. Tianjin in the People's Republic of China has two very special systems of traffic lights, in use since : One system is where there is a horizontal bar in a specific colour, with the colour changing and the bar shrinking. The shrinking bar indicates the time remaining in that colour. The colour itself is either red (stop), yellow or green (go). A blinking green one-third-full bar means "reduce speed now", and a blinking yellow full-bar indicates "proceed with caution". When lights of this system turn from green to red, the diminishing green bar will flash
Light characteristic Light characteristic A light characteristic is a graphic and text description of a navigational light sequence or colour displayed on a nautical chart or in a Light List with the chart symbol for a lighthouse, lightvessel, buoy or sea mark with a light on it. The graphic indicates how the real light may be identified when looking at its actual light output type or sequence. Different lights use different colours, frequencies and light patterns, so mariners can identify which light they are seeing. While light characteristics can be described in prose, e.g. "Flashing white every three seconds", lists of lights