Models listed in the Model Panel may contain molecules or other items, such as surfaces or VRML objects. Once a model has been chosen in the left side of the Model Panel, clicking the attributes... button in the right side of the panel brings up a window that shows and allows changes in model attribute values.
Attribute descriptions within these panels are not necessarily the same as the attribute names; separate tables show attribute names for atoms, residues, and molecule models, as well as how they can be used for atom specification in the Command Line.