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Keywords from Image Description:
NS lichtseinstelsel groen groen wit. en Threehead searchlightstyle railway signal of the railway signalling system of the Dutch railways Greengreenwhite high speed reduce to medium speed nl Driehoogtesein van het lichtseinstelsel van de Nederlandse Spoorwegen Groengroenwit hoge snelheid volgende sein toont middensnelheid own