4 1/2 Inch Solid Brass Ball-in-Hand Door Knocker (Polished Brass Finish) - constructed from solid brass and hand finished, each knocker measures 4 1/2 inch tall by 1 1/2 inch wide. The approximate projection is 2 inch and this is a reverse mount door knocker. This stylish door knocker comes with a matching circular strike. This door knocker mounts with a single machine screw (included). This item is made from solid brass and it is available in a variety of finishes. It is also available in solid iron.