Montane’s PETRICHOR 3-layer technology delivers waterproof (20,000mm Hydrostatic Head), exceptionally breathable performance to the Cetus Jacket. It scores a RET rating of less than 7, which means it is ideally suited for high-output activities in the outdoors, where it will remain breathable to keep you dry inside and out. This is achieved through the windproof, non-porous hydrophilic membrane that transports water vapour and moisture away from the body, an effect that increases in strength as you work harder. The 3-layer construction sandwiches the waterproof membrane between a 100% recycled, 30D Ripstop nylon face fabric and the lining, for improved durability and next-to-skin comfort.