...
The "Credit Note (create)" form. The Inventory tab
If the credit note is generated based on the invoice, this tab is automatically populated - remove the lines that you don't need and leave the lines with returned items or the items for which correction is needed and edit the details.
If you need to manually add an item or multiple items, click the Add button.
In the Quantity column, you can specify the item quantity and in the Unit column, you can select an UOM for the item if the Multiple UOMs per Item option is selected on the Administration > Settings > Purchasing and Warehouses form.
The Characteristic column is available if the Enable Item Characteristics option is selected on the Administration > Settings > Purchasing and Warehouses form. In this column, you can specify additional properties (such as size, color, and so forth) of each item if the Use Characteristics option is selected for the item in its master record (see Items).
The Batch column is available, if the Enable Batches option is selected on the Administration > Settings > Purchasing and Warehouses form. In this column, you can specify the batch (lot) number for the items for which the Use Batches option is selected. Generally, you must specify batch numbers for items with expiration dates, items used in consignment or stocked in contract warehouses. To learn more about the item settings, see Settings: Purchasing and Warehouses.
...