With winter kit in the dead of winter for 2 months tested: Since the ventilation holes can be closed, I was always dry, helmet fits well, is warm enough even at -15 ° C. Summer experiences are still pending. Funny: the integrated rear light, however, the pressure switch in freezing temperatures is a little stiff, that's difficult to turn on the lamp after the ride. Compared to similar helmet (from Giro) belt adjustment is friemelig.