Louis Garneau Matrix 2.0 HatThe Louis Garneau Matrix 2.0 Hat is aimed rides during those cooler months, and it features what the company calls Matrix 2.0 fabric with a multizone knit pattern for comfort. That gives it breathability where needed, without any added bulk. The seam design minimizes chafing, so you won't even notice it's there.FeaturesInsulation type: SyntheticSeason: Cool weatherSize: One sizeSizeHead Circumference (in)Head Circumference (cm)One Size20.5 - 25.7552 - 65