The blame should be put squarely on the shoulders of tophatter.com. They know the quality of what is being sold and choose to look the other way for the sake of making commission and sales fees on these imitation goods. In my estimation and also the interpretation of the law this is outright FRAUD.
Inverse operations are opposite operations that undo each other. Addition and subtraction are inverse operations. Multiplication and division are inverse operations.
Undo is a command in many computer programs. It erases the last change done to the document reverting it to an older state. In some more advanced programs such as graphic processing, undo will negate the last command done to the file being edited. The opposite of undo is redo.