The Kokatat Hydrus 3L Launch Sock feature Hydrus 3L, our proprietary waterproof breathable 3-layer fabric designed to keep your feet completely dry in extreme conditions. The super tough nylon woven outer layer provides long lasting abrasion protection and features a durable water repellent (DWR) coating which repels water. The mid-layer utilizes a polyurethane micro-porous coating, allowing water vapor to transfer from the inner layer to the outer. The soft, knit polyester inner layer is engineered to help manage moisture, moving it from the inside out. The result is an exceptionally waterproof breathable alternative that stays dry and comfortable. Kokatat Hydrus 3L garments are backed by a lifetime warranty against defects in materials and workmanship.