When the wind blows through a garment that's not windproof, it destroys the warm layer of air next to your skin — your microclimate. You start to feel uncomfortable almost immediately. Just think about how many times you've retreated indoors when the windchill temperature was -10° F/-23° C, even though the thermostat read 40° F/4° C. It's that windchill effect: it makes everything colder. With GORE-TEX® INFINIUM® with WINDSTOPPER® technology fabric, your clothing is totally windproof, so you can stay outdoors longer.