Symbol 1310 from ISO 7000 - Title/Meaning: Special tools 
Function/description: To indicate that special tools are required for maintenance, assembly, or disassembly of the equipment.
Own work using: iso.org/obp/graphics/grs/47a7c398-8c64-4d71-a3d7-cb3db8b62363 200.png
Vectorization:  Mrmw