The steel posts that we use to support our heavy duty mailboxes:
5″ x 5″ x 57″ Long for the Large Standard, Fortress, Vacationer, Senator and Package Box.
If you have a preexisting post, make sure it can support our mailbox weight.
The post comes separate from the mailbox and is bolted from underneath with “carriage bolts,” so that no theft of the mailbox is possible. This is also ideal if you move, and want to take the mailbox with you instead of pulling the steel post out of the concrete. Posts are made of 10 gauge square tubing. (10 gauge = 1/8″). The posts are buried in 2+ feet of concrete.