Integration with Other Applications > Managing CAD and Part Relationships in Windchill > Customizing Auto Associate > Modifying the Implementation to Search for Customized Parts or Custom Parts
  
Modifying the Implementation to Search for Customized Parts or Custom Parts
When performing searches, the default implementation is to search for a Windchill part.
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When you create a customized part, its master must be WTPartMaster or a subclass of WTPartMaster. The customized part itself must be a WTPart or a subclass of WTPart.
To customize the implementation to search for a customized part that has been implemented in the codebase (for example, wt.part.MyCustomPartMaster), set the preference, Operation > Auto Associate > Custom Class for Auto Associate Part to wt.part.MyCustomPartMaster.