This 14in X 21in HY-C Stainless Steel Big Top is the Cadillac of our chimney cap line. It has a heavy 18-gauge mesh with a 24-gauge lid. It is 100 percent 304-stainless steel and features scalloped corners and rolled edges. The base tabs mount to the chimney crown with masonry screws and a 10.6 oz. tube of adhesive included.