When you create or update a product, you'll notice there are two different fields where a description can be placed - description and unit description. It's important to know how these fields work in order to understand how product information will appear on defect quotes and invoices.
Where to input description and unit description
When updating/creating a product:
Description field is in the details section
Unit description field is in the billing section
Description - defect quotes
When you add the product as a line item in a defect quote, it will display the information from the description field of the product.
Unit description - invoices
When an invoice is generated from the task it will display information from the billing field of the product.
Exceptions
Invoices for Fixed Billing Contracts will use the description and not the unit description.