The Swap button in Sage 50!

Whenever I visit a customer to do training I ask them if they know what the "Swap" button is that appears on all the menus.  Most people have no idea!  Basically it is designed so that if you select a single record (e.g. you select a customer in the list) or a couple of records, when you hit the swap button it reverses the highlights so that all the customers are highlighted except the ones you originally highlighted.  Therefore the highlights are swapped!!