had used the glasses for the site, hardness testing! Did my eyes well protected however it is very fast on the glass scratched so that they are more likely to be frosted glass! Also, it is relatively difficult to get the glasses so thick that reinzieht little or no dust! From the processing is nothing wrong negative, band is easy to adjust and well connected with the glasses! Very stable! Result: for rough work such as wall raushauen ideally suited for wandabschleifen less because dust gets into the glasses!