Instead of using a petroleum-based lining to make them waterproof; these eco-friendly paper cups use a plant-based resin that is sturdy enough to withstand hot beverages. The 100 percent natural resin is also an annually renewable resource. The hot beverage cups hold up to 16 oz. and offer a rolled rim at the top for durability and comfort. Rim is designed to accept both flat and domed lids. Lids are not included. Cups are not recommended for iced drinks.