Brass Finished Cast Iron Mermaid Door KnockerMermaids (and pirates & octopuses) are part of the Steampunk genre, which is where we started and why we also have a soft spot for them. Don't have an outside door to mount on? Why not the bathroom? Bedroom? Dungeon? Or any other door? 5" tall, 4" wide and 1" deep. Two mounting holes, brass painted finish A note on our cast iron items: All of these are sand cast. The surfaces can have bumps and other irregularities, and the painted finishes will vary