A sundry line in an invoice is usually used for products not normally kept in stock.
To enter a sundry line in a customer invoice:
Go to Customers, Transactions, Invoices, Create.
Enter the Customer Code and related information in the invoice header section, and tab through to the body section line 1.
In the body section of the invoice, Click the Section (F4) button in the toolbar or function buttons at the bottom.
Select the Sundry Line option.
The line then changes to a sundry line format.
Enter your details and create the invoice as normal.