A chimney chase is a chimney by any other name, but usually one built of framed wood or siding. It is essentially a prefab chimney made of wood. Every chimney cap and top below will be made to order according to your exact specifications, you can pick from a variety of metals for your chimney cap. Lead coated copper, aluminum, and zinc. MISSISSIPPI LICENSE: #07256 Or schedule online by clicking here Most prefabricated chimney caps are brand-specific, factory-designed to either twist-lock into place or constructed as "drop-ins" that require fasteners. For a twist-lock chimney cap, the bottom of the cap will feature the same type of lance system that the chimney pipe itself used, allowing the cap to simply twist recommended grout cleaner and lock into position. Once fully locked, two to three self-tapping sheet metal screws can be installed around the base of the perimeter to ensure the chimney cap does not loosen over time.