Not suitable for all types of glass

The cloth is relatively small, only just fits a modern spectacle, and has roughly the consistency of a miniaturized terry towel, ie it is relatively thick and therefore do not always fit together with the glasses in a small spectacle.

In the first 2-3 "Applications" fusselte the cloth of clearly visible, but cleaned after a few times quite passable.
After about 10 ~ 20 applications, it began to turn to fluff, but the cloth was now tiny, barely visible white filaments on the lens back, affecting the viewing easy. At this stage, it was no longer possible to remove the same filaments using the cloth itself, as more new filaments and tiny dust particles generated on the glass.

The subsequent washing test in the machine (without fabric softener, of course!) Survived the cloth quite well, the problem with the tiny fiber residues on the lens remained however.

When testing with different lenses made of plastic (!), The problem occurred with the filaments partially almost no longer occur. The cloth seem to react differently to different types of glass. However, Scattered, barely perceptible "Microfussel" could be completely avoided in any test. So there is no choice, as the thing to test individually ...

So far me not a single microfiber cloth is known, which works in the long term - no matter what brand.
The best cleaning results are achieved still in the ultrasonic cleaner with water and a mild detergent.
Who wants to buy an ultrasonic cleaner, can use a water bowl with a little detergent.

As a stopgap measure for the road help the classic Brillenputztücher, which are offered at good optician. These hold depending on the application about two months before they need to be replaced.