Lets say, that you have a transaction over 100,- and use Partial Captures to capture 50,- , 20,- and 30,-. You can refund these individual parts and Saferpay will make sure, that the amount of these parts will not be exceeded, even if multiple refunds are executed. This means, that you have to refund each individual part, with this option enabled, in order to refund the whole transaction, as Saferpay will not allow you to refund 100,- on just one part (as it is possible without this option enabled). Likewise, if you want to refund 75,- , you first must refund the 50,- and then 25,- of the 30,- or the 20,- and the remaining 5,- from the 30,-. Of course, you can ignore this detail, if you execute a normal capture or just one Partial Capture over the whole transaction amount.