The top ledges of your pool compose the top ring of the pool. They are important because they are the part you see the most while you are in the pool, with the exception of the liner. They are also the only part of the pool horizontally exposed to the sun and water. Generally, they are made from either galvanized steel, resin coated steel, or resin. Resin is considered the better material because it simply can never rust and stays cooler to the touch. Steel ledges are a great alternative because they are strong and economical. They have many layers of protection to prevent rust and corrosion.