To be honest, I did not expect this after all the laudatory reviews and reviews, but the vents 100 ma, which costs half the price, is better in almost everything, except that it makes noise at 36 dB, and not 34 like this one. Silent will stand for now, but if in the summer there is a reverse flow of air through the ventilation shaft, you will have to change it again due to the lack of a normal check valve.