This image was acquired from
wikimedia. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
ZIS Lesestelle. de Lesestelle des ZugIdentifikationssystems ZIS bei der UBahn der Berliner Verkehrsbetriebe BVG own Bukk Berlin UBahn Rail transport traffic control
Page 2023 Free-images.com. All images are Public Domain