You can have a commodity code appear on your export invoice, this is an extra option to print from invoicing.

<Invoice><Actions><Print Export Invoice>

If this is not an option for you give support a call and we can set this up.

To set up your commodity codes an administrator can do this by going to <Tools><Setup><Options/Checks><Deliveries and Invoicing>

You can add your commodity code by pressing the + button at the bottom.

To have the commodity code show up on the invoice itself you have to add it on the works order that line is from.

<Works Order><Financial/Costs><Commodity Code>