Symbol 5537 from IEC 60417 - Title/Meaning: Fader Function/description: To identify the controls for picture fade-in and fade-out.
Additional information: 
Published in: Supplement M, 1994
Own work using: iso.org/obp/graphics/grs/eeaf902c-6d0c-410d-90b9-a5bade3af460 200.png
Vectorization:  Mrmw