ISO/TS 10303-1156:2005 specifies the application module for Product structure and classification. The following are within the scope of ISO/TS 10303-1156:2005: the existence of an individual product; a whole-part relationship between two individual products; a connection relationship between two individual products; a containment relationship between two individual products; an involvement of a individual product in a connection between individual products; the existence of a class of product; a mapping between one class of product and another that indicates the nature of a whole-part relationship between two individual products; a mapping between one class of product and another that indicates the nature of a connection relationship between two individual products; a mapping between one class of product and another that indicates the nature of a containment relationship between two individual products; a mapping between a class of product and a class of connection of product that indicates the nature of an involvement of an individual product in a connection; set theory relationships, such as subset, union and intersection, between classes of product and between mappings; the classification of an individual product as a member of a class of product; the classification of a relationship between individual products as a member of a mapping; the specification of the complete membership of a class of product or of a mapping between classes of product; reference to an externally defined class of product or product relationship.