Extending Material Master Records 
Use
If one user department has already stored data on a material in a material master record, and you work in another user department and want to enter data on the same material, you do not have to create another material master record. Instead, you extend it to include the information relevant to your own user department.
You also extend a material master record if the same user department wants it to include data for other organizational levels.
Example
You create a material master record for the user department Purchasing , but do not specify a plant. In this case, you can maintain only data at client level. You subsequently want to maintain purchasing data for a specific plant. You do this by extending the material master record and specifying the plant concerned. You can now enter data at plant level, but not change the data you have already entered at client level.
Integration
Maintenance Statuses
The maintenance status of a material master record is important for extending such records. This indicator, which is set in a material master record when a user department creates data for a material, allows you to see what departmental data has already been entered. For an overview of the maintenance statuses defined in the material master, see Maintenance Statuses .
To maintain all material master records as fully as possible, users need the following information:
User departments that need to extend a material master record
Material master records that a user department needs to extend
For a description of how to obtain this information, see Finding Information for Extending Material Master Records .
Mass Maintenance
Using a special cross-application tool, you can extend several material master records at the same time. However, this tool must be used only by experienced users. For more information, see the SAP library documentation Cross-Application Mass Maintenance (CA-GTF-MS) .