Durable, stretch-woven nylon coated with DWR seals out dust, debris and unexpected rain showers, while allowing your feet to breathe during high-output activities like trail running or fast and light hiking. A low-profile and extremely tough instep strap tucks up and out of the way so it won't slow you down. And for a quick getaway, the gaiter can be kept on your shoes as an entire unit between adventures.