Symbol 5234 from IEC 60417 - Title/Meaning: High water level Function/description: To identify the control by which a high water level may be selected.
Additional information: 
Published in: Supplement E, 1980
Own work using: iso.org/obp/graphics/grs/bbda8d5a-5138-41c6-a7ef-84e1e8d480ef 200.png
Vectorization:  Mrmw