Montbell Down Jacket Men's Permafrost Light Down Jacket (WINDSTOPPER® fabrics by GORE‑TEX LABS)Permafrost x GORE WINDSTOPPER. Wind blocking flagship warmth. The Permafrost Light Down Jacket in WINDSTOPPER (GORE TEX LABS) fabric pairs 800FP down with a wind impermeable membrane engineered for cold, exposed conditions where wind, not rain, is the threat. Pinnacle materials 800 FP EX Down premium European down WINDSTOPPER fabric by GORE TEX LABS totally windproof, breathable Slim alpine cut layers under shell Where it shines Cold and windy alpine,