* active settings "Allow using different units of measure" in Settings > Configuration > Sales >  Quotations and Sales Orders >  Product Features


* During the creation of a category, tick the box 'To Weigh With Scale'.

.. image:: ../static/description/uom_category_form.png
   :alt: Change the field 'To Weigh With Scale' for every weighable category
   :width: 400

Note: During the installation, the UoM Category 'Weight' is checked.
