Our StormTek™ waterproof/breathable ePTFE technology is storm rated to 23,000mm waterproofness and an MVTR of 21,000g/m², both at the top end of the performance range for 3-layer fabrics. The outer shell is a 40D nylon mini ripstop with C6 DWR, bonded to the membrane and a 30D wicking PES inner layer that manages moisture against base la