ItemID 15663 Door Knocker. Once a sign of their homeowner's profession, doorknockers now come in a variety of designs and finishes for everyone's style. Step-up your curb appeal and add value to your home with finishing touches like a knocker. Made of 100% black cast iron with our Exclusive rust-resistant RSF powder coat finish make this knocker a knock out! Easy installation, thread bolts through the door for secure mounting. Mounting hardware included. Measures 7 in. H x 2 1/2 in. W.