The Properties tab is one of the product tabs which appears with product details in each of these screens: the Product Catalogues screen, the Search screen or when you view Supplier List > Individual Prices
Open the Product Catalogues window and locate a product using the Search options to access these options on the Properties tab
Most product types will show you data for:
Height (mm)
Weight (mm)
Depth (mm)
Gross weight (kg)
EAN (product barcode number)
You can add or change the data that has been included already by clicking the Edit icon at the top right.
Once you have edited the detail, click Save to store your overrides. Note that any overrides you have made will be persistent in your data, including after you have updated the catalogues from EQ again.
You can remove your overrides by returning to edit this tab.