To create a complete system, select a post, mailbox and additional options below. Post is made of durable, rust free cast aluminum. Solid brass numbers available. Some models also available in twin configurations call for details. Address plates 1, 2, and 3, cannot be mounted on the Classic Manor Post #1, Westchester, or Balboa. A note about metal casting: Cast aluminum products are first poured in a sand mould that does not allow perfection in every detail. But that's the appeal of such castings. These "accidentals of art" lend an Old World charm to each piece that no artist could fashion intentionally. In effect, each one is a unique creation.