Polaris Cranium helmet liner review
Super-ventilated helmets are all well and good in the height of summer, but as winter approaches keeping your head warm becomes more important. This super-thin hat is designed to ﬁt unobtrusively under your lid.
It’s made of stretchy ﬂeece on top, with windproof panels over the forehead and ears, and it’s shaped to ﬁt snugly over your ears. It’s very effective without being too hot, which is a problem we’ve had with some similar hats.