Symbol 0984 from ISO 7000 - Title/Meaning: Block Function/description: To indicate a reference to a program block.
Additional information: 
Symbol used to identify and qualify functions which relate specifically to program blocks.
Own work using: iso.org/obp/graphics/grs/1cad6e63-fae8-4974-811c-7eb6e31db1a7 200.png
Vectorization:  Mrmw