The first thing you'll notice about the Hy-C Cap is its unique corner installation feature. The slotted hex-head mounting bolts are indented into the base to give the cap an even, secure grip against the flue tile. You'll also notice how the lower edges of the mesh screen are folded inward. This gives a complete, firm base resting on the flue tile-you won't see any critters climbing under this cap. The Hy-C 304 stainless steel chimney cap has a 24-ga. single-piece top with smooth, rolled edges. The 18-ga., 3/4" mesh screen is 6 1/2" high. It has a lifetime warranty.