Description of The North Face Windwall 1 Jacket Windproof protection for cold weather changes is necessary for any outdoor explorer. The Windwall 1 is a lightweight, windproof jacket ideal for aerobic activities or as a layering piece in windy conditions. Designed for athletic movement, The North Face Windwall 1 stands up to hard core use. Fabric bonding limits air permeability and increases your comfort, while elastic cuffs and a hem cinchcord trap in body heat and keep out the cold air. Classic fleece style and windproof warmth for outdoor adventures in The North Face Windwall 1. Features: 20 CFM(Cubic Feet per Minute) : Measures the number of cubic feet of air that can pass through a square foot of fabric in one minute at a pressure differential equal to 30mph wind speed. Ranges from 0 (no air permeability) to 100 (high air permeability). Hem cinchcord Two hand pockets Proprietary wind-blocking, breatheable fleece jacket with low air permeability for aerobic activities.