Item list is needed for you to choose whether to display only products, services or both elements in the printed document.
In Bitrix24, there is a document as an entity, such as a delivery receipt or sale document, and there is a printed form of the document, which is created according to a certain template. The Item list option affects only the printed form of the document, i.e. the information that goes into the document file.
Let's say you are engaged in the equipment installation. In the deal, the manager specifies the product and the service: air conditioning and air conditioning installation. When finishing the deal, the employee prints two documents: the report of work performed and the invoice.
To customize a template, click the item menu and select Edit.
Click on the Item list field and select the desired value. Don't forget to save your changes.
Only the selected type will be displayed in the document. If you selected Services, the products you added to the entity form will not be displayed in the document.