To specify the conditions when the part should be included in the product structure, you can assign expressions to the usage links of children of configurable modules or directly to child parts. Assigned expressions reference the options choices that are included in the option set. After you assign expressions, you can filter the product structure using the Option Filter to create discrete product configurations.

The Option Filter uses a list of predefined options and choices, contained in the assigned option set. Based on the design specification for the product variant, you can specify the filtering criteria and apply them to the product structure to produce a desired product configuration.

The next diagram illustrates the main steps for creating product configurations in Windchill using list-based option selection process.