Only one pen works

Unfortunately, it is no longer possible after a month to 0.5-and 0.35er to use, because the mine does not come out.
Too bad that is 0.7er fine.
Nevertheless, pay for 3 pens, then only one can expect any buyer to use a.

Conclusion: better to invest a little more and then try the Grip Plus from the same house. With whom I have no problems.