Feature cells are special cells that have been created using global variables and equations, grouped in a parameter set, to define their parameters.

One feature cell can have multiple parameter sets, one of which you select when placing the cell. As well as fixed dimensions, parameter sets can include variable or "free" parameters, which you define when placing the feature cell.

Sets of the parameters then are created in a Parameter Sets Table, thus letting you use the one cell, with different dimensions applied to the various parameters.

When you place a feature cell, you also select a parameter set from the table, which is used to construct the cell. Parameters can be defined from global variables, and equations. They can be fixed (not editable) or free (editable) at placement time.