Whether pinning it up a ridge or ripping through deep snow, the newly-updated 509 Allied Insulated Mono Suit provides excellent weather protection with fully seam-taped, waterproof/breathable fabric, low-bulk Thinsulate insulation throughout and burly, triple-stitched Cordura 300D polyester. An updated crotch gusset improves fit where you need it while a new zipper fly makes pit stops a breeze.