This chimney cap is fabricated with copper, pre patina copper, stainless steel, freedom gray, TCSII, lead coated copper or zinc.. Its roof is attached via brass or stainless steel nuts and bolts, this way the interior of the cap can be cleaned at any time. The screen used is a rigid 14GA expanded copper/stainless sheet. All seams are soldered and/or riveted, unless otherwise specified. Material thickness is subject to change as per customers specifications. Riverside Sheet Metal