Symbol 6334A from IEC 60417 - Title/Meaning: Selection; affirmative acknowledgement; success; ACK Function/description: To identify the control to acknowledge affirmatively and to indicate the status of acknowledgement, or to indicate the successful status.
Additional information: 
See also ISO 7000-0422 and ISO 7000-1940.
Own work using: iso.org/obp/graphics/grs/30388b91-9316-4fcb-b383-fbeec1a0d337 200.png
Vectorization:  Mrmw