I got the model with the adjustable feature, usually I take a 61 cm helmet, the xl fit fine. I did not like the fit of the POC helmets at first. I guess my head is the wrong shape. But the adjustable slides on the back of the helmet tailorthe helmet to a perfect fit. I teamed them with POC goggles, and like that there is no gap between the helmet and goggles. Now if I can just get the brim to snap into place it will nbe perfect.