Source the Units Type of the Item Using Custom Transaction Line Fields

1. Navigate to Customization > Lists, Records, & Fields > Transaction Line Fields > Click New.

2. Set Label field to Units Type

3. Set Type field to List/Record.

4. Set List/Record field to Units Type.
5. Unmark the Store Value field.
6. In Applies To tab > mark Sale Item checkbox.
7. Click the Sourcing and Filtering tab, set Source Lists field to Items and Source From field to Units Type.
8. Click the Display tab and set Display Type to Disabled.
9. Click Save.