If you go to the Menu - File - Properties and look at the default property list you have a list of default properties, one is part number.
If you go to property tab builder, create the textbox box, under valve there is no listing for "part number" which is a default property.
I can do everything I need with the default properties and it would keep things simple with no custom properties.
What don't I understand correctly? How do I deal with this and make it work?