Create Attributes on Links (SolidWorks ePDM)

Hello

I want to create new attributes on the links between 3D in ePDM (like quantity).

I want to access the information in the BOM views.

For example, to process the unit of measurement of a component or to put an indication of the use of the part in this context.

It would also allow me to categorize the links I make when I want to attach documentation for example.

Do you know how to do that? 

Thank you in advance,