Explanation
A scheduling agreement is a long-term agreement with a vendor for the supply of materials or services according to a predefined delivery schedule. Some features of a scheduling agreement are:
A material master record is optional in a scheduling agreement item. You can use item category M (Material unknown) to enter a short text and material group instead of a material number.
A scheduling agreement can be used for a consignment process. You can use item category K (Consignment) to indicate that the materials are stored at your premises but are still owned by the vendor until you consume them.
A scheduling agreement item is always plant-specific. You must specify a plant for each scheduling agreement item and you cannot change it afterwards. References: SAP S/4HANA Sourcing and Procurement | SAP Learning, Course S4520, Unit 5, Lesson 1.