Often when creating your job estimate, you'll need to add both quantities and units of measure, or, as they're commonly referred, UoM.
You can easily create your own UoMs - but you'll need to do so ahead-of-time, as you won't be able to create the UoM once you're in the job edit mode.
To create a new UoM:
• go to Admin >> Items >> Units of Measure
• click the blue New Unit of Measure button (upper-left)
• enter a name and an optional abbreviation and/or description
• click the blue Create Unit of Measure button to create your new UoM
You'll now be able to see and select your new UoM when you next create your estimate line items.