BIO Waterproof, a bio-based membrane technology, uses plant-based sources to deliver the same reliable all-weather protection and comfort you have come to expect from eVent fabrics. Light, tough, and flexible, BIO Waterproof offers unparalleled comfort for days when you know it is going to be wet or snowy. Paired with recycled or other smartly sourced fabrics with a C0 DWR, this sustainable technology has a reduced carbon footprint.