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To add characteristics to the newly created category, click the Characteristics link on the top of the form. The Item Category (Item Characteristics)
form appears. Initially, the list of category's characteristics is empty.
The list of Characteristics defined for the category initially
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The list of Characteristics defined for the category
Adding an UOM for the Category
To add units of measure to the item category, save this category, and click the UOMs link at the top of the Item Category dialog box.
This opens the Item Units of Measure (create) dialog box.
The Item Unit of Measure (create) dialog box
In the Description field, type a string designating the UOM. Click Save and close.