In context of overlay "Things" – Underground Fire Hydrant – https://osm.org/node/13274034417 via StreetComplete 63.0:

Hier "B" Hydrant unter Schachtdeckel

Attached photo(s):
https://streetcomplete.app/p/332492.jpg
https://streetcomplete.app/p/332493.jpg
https://streetcomplete.app/p/332494.jpg