Click the PathFinder tab.
In PathFinder, click a component that is in the active assembly.
On the shortcut menu, click Define Alternate Components.
In the Define Alternate Components dialog box, search or browse for the documents you want to be candidates for alternate components.
In the Define Alternate Components dialog box, click the Add button to add the documents you defined in the previous step to the Alternates list, then click OK.
Tip:
When you define a list of components as an alternate components group, they are not required to be the same document type. For example, you can specify that a part document (*.PAR) and a sheet document (*.PSM) are members of the same alternate components group.
A group of alternate components make it easier to define a replacement part when replacing a component in an assembly.
You can also use alternate components when defining member characteristics for a family of assemblies.