Key operation difficult

that's the problem why I forgive only 3 stars. The optic is in fact great.
Sometimes one uses the power button ausversehens or 2 times, since they are apparently not prepared properly.
Have now tried the keys cut, which does not even make the operation more convenient.

Incidentally, I have not bought a 2nd envelope (the black S-TPU). If your the formations for the side Tasen look different and they can be operated properly. Would be interesting to know whether the transparent black shell (S-TPU) is also working so. Just try to contact the seller.

Addendum 20.01.2014: the consignor I get free nor transparent sheath S TPU sent - great service. In this envelope the key operation works!