Hi! I’m new in this world… sorry for the stupid question… 
I’ve started this diagram
The first i used the id of revit, the second a sequence created by me… now i would to add a Lecter before the sequence, how can I do?
Are you wanting to take the ID’s value, append a character in the front and set it to your project parameter?
Here are some ways of doing what (I think it is) you want to do:
@J0hnp
I’m working for a ID’s value in the proprieties of the object in Revit
@Andreas Dickmann
no… but something of similar
now I’ll work to make it fit my needs, I’ve to use the node “Element.set.parameterByName” and this is incompatible with the value of the node