Symbol 3881 from ISO 7000 - Title/Meaning: Test weight 
Function/description: To identify the control that sets the test weight to be used in calibrating the weight-measurement instrument. To indicate the test weight.
Own work using: iso.org/obp/graphics/grs/6b794514-b2d4-4d81-90d0-9482f03ac74a 200.png
Vectorization:  Mrmw