When used properly, a tight-fitting gaiter will keep mud from entering the ankle collar of boots and hiking shoes. Additionally, gaiters should provide coverage to the foot instep (the top of your foot) reducing the chances for mud and debris to enter shoes in gaps created by lacing and the tongue. Waterproof fabrics or fabrics treated to be water resistant will be the best defense against mud. These fabrics can also be the easiest to quickly clean and dry. For this specific thru-hike in the Adirondacks, coverage from mud was the primary use case for the gaiters on this list. My hiking partner and I wore shorts and non-waterproof shoes for a majority of the hiking. We knew water and mud was going to be an issue, and the ultralight gaiters layered on top of our standard footwear kept our legs and socks cleaner, and therefore dryer, than they would have been otherwise.