The Gelco Stainless Steel Multi-Flue Chimney Top Cap is the cap to use when you come across multiple, odd-sized or unlined flues. You can even use this cap for a single-flue because they cover the entire chimney crown. Tops are constructed of 304 stainless steel, have a screen height of 8" with 3/4" mesh, and come with a lifetime warranty. Masonry fasteners and mounting adhesive are included with each top. Weld nuts on the top mounting strip give you a choice of two ways to attach the lid. Use traditional cap screws or use our wing nut option. Both are included.