Supplements are side articles that can be connected to another article (I.E. extra cheese on a pizza). The difference between supplements and modefiers is that supplements have a extra price and modefiers not.
To add a supplement select the tab ‘Supplement’.
Select the department of the supplement and click on the add button (+).
Type the name of the supplement, the price and the TAX rate. Select the options on the right.
Save the supplement by clicking the accept button at the bottom.