Castelli Estremo WS Berretto, nero

Castelli's warmest winter cap has GORE-TEX Infinium Windstopper protection on the front-facing surfaces, while we let sweat escape out the back with Warmer fabric. It's thick enough to provide warmth but takes minimal space under the helmet.

GORE-TEX Infinium Windstopper
Experience total windproofness and maximum breathability for comfort in cool and windy conditions. The light, breathable membrane blocks the wind while allowing vapors to escape, keeping chill effects to a minimum. An additional layer is available in some GORE-TEX Infinium Windstopper products for more protection and insulation. Durable treatment to the outer layer provides a complete shield against the wind and is highly water resistant.