The Spec 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 Spec tab.
If the product has a specification within the catalogue you can amend it, or add your own to a blank specification.
Click the Edit button and edit the text in the text box.
Click Update to save.
Clicking Reset returns to the catalogue specification, or a blank box if there wasn't one.