The Feil result is top and so far the best of all glass files I've tried. The nails do not fray, it results in a smooth, clean cut, because the file is very sharp. What leads me to the bad review: after 3 x use simply broken apart while filing. It is to me before wohlbemerkt fell down NIE which I exclude hairline cracks times. I have the same Problem with other reviews so gefunden..ist something to it. This should at a BRAND file and for that price just does not happen!