Datasource for Delivery Document

Dear All.

There are two data sources 2LIS_11_V_SSL (Sales Document : Order Delivery) and the other is 2LIS_12_VCITM (Delivery Item Data).

Both data sources are providing information related to the delivery 2LIS_11_V_SSL contain the fields Sales Document, Sales Item, Delivery and Delivery number which is enough for generating information related to deliveries, then what is the benefit or use of 2LIS_12_VCITM.

Can you please guide that for making DSO for deliveries which data source to be use.

Please explain little more about the boths

Kind regards,