OutDry uses a one piece patented construction process that creates a waterproof breathable barrier. This impenetrable layer is heat bonded directly to the outer fabric, leaving no seams, no gaps, and no way for water to get in. Compare that to traditional waterproof technology. Water gets in and stays in, collecting in the space between the inner and outer layers, making them heavy and wet. OutDry improves fit and dexterity, keeping you drier, lighter and more comfortable.