I bought these headphones to isolate myself complement openspace of a proper asset-ear with noise but not enough to face non-cyclic noise. The helmet insulates the sound is quite correct. As against it is not very easy to adjust and he squeezes hard enough ears. (Not great with glasses I have not tried by plane but I will test at an upcoming trip despite its bulk. In the end, for less than 40 euros good insulation and a good quality product