The cup used for the first time after purchase was suddenly broken. Even if you contact the manufacturer, it was that it was too much power. (It used to be properly used but it seemed to be suspected even though it was alright.) It is a tool to loosen tightening tool but it is meaningless if it can not be loosened. Although it can be convinced if it is a cheap maker. . . Other cups purchased with the set were also discarded as there are problems in use.