A part that is sold as a service part and also used as a component in another part is called a dual-sourced item. A dual-sourced item has two sources of demand: the external demand from the customers who buy the service part, and the internal demand from the parent part that uses the component. The planning for a dual-sourced item should include both sources of demand in the gross requirements, so that the net requirements can be calculated correctly. The service part demand can be included in the gross requirements by using a planning bill of material, which is a special bill of material that shows the relationship between a parent item and its service parts. A planning bill of material allows the system to explode the service part demand to the component level and generate planned orders for both the service part and the component.

The other statements about the planning for this part are false. Its low-level code is not zero, because it is not an independent item. It has a higher low-level code than its parent item, because it is a component of another item. The material requirements for the part will not be understated, if both sources of demand are included in the gross requirements. It should have some safety stock, to protect against demand and supply uncertainties. References: CPIM Part 2 Exam Content Manual, Domain 4: Plan and Manage Supply, Section 4.2: Material Requirements Planning (MRP), p. 22-23.