Symbol 5845 from IEC 60417 - Title/Meaning: Inner diameter Function/description: To indicate a reference to the inner diameter.
Additional information: 
Published in: 3C/797/FDIS
Own work using: iso.org/obp/graphics/grs/7ff669bd-e766-4295-bcf9-7322bc998b0d 200.png
Vectorization:  Mrmw