What's in a mailbox?

Traditional Mailbox

Mailboxes are classified in three different groups: Traditional, Contemporary, and Locked.  Traditional mailboxes are just that, your everyday rectangular mailboxes with the arched roof, a hook handle on the front, a red flag on the right side, and U.S. Mail in big bold letters on the front.
Contemporary mailboxes are mailboxes of other designs and/or materials that fit within the standard dimensions.  These mailboxes are found in stores like The Home Depot, Lowes, Wal-Mart, and most hardware stores. 

Oregon Columbia Mailbox

Locking mailboxes have less stringent requirements for dimensions but have similar functional requirements.  For example, locking mailboxes with a mail slot must have an opening no smaller than 1.75" high by 10" wide.  

 Our Oregon Columbia mailbox is an example of a locking mailbox with a slot design.  It conforms to the U.S. Postal Service requirements by having a slot that is 2 1/8" high by 10 1/8" wide.  

One of our best value mailboxes, the Oregon Columbia provides what Traditional, Contemporary, and even other locking mailboxes do not: security and peace of mind.  It features 20 gauge riveted steel with a 12 gauge steel door and is locked with a double-sided key that provides exceptional security at an exceptional value.  

Traditional and Contemporary mailboxes have one major flaw.  Security.  The Locking variety have an obvious advantage, but a mailbox with a lock on it does not automatically make it secure.  Locking mailboxes that are poorly designed and/or are made with low quality materials are little better than Traditional and Contemporary mailboxes.  The security of a locking mailbox made from plastic or thin and weak metals can easily be defeated with simple hand tools or just brute force.  The locks themselves are a key part of the security, as you would expect.  A poor quality lock can be drilled out in under 1 second with your average cordless drill (believe me, I've done it!).  On the other hand, a high-quality lock can take up to 30 minutes to an hour or more (and multiple drill bits) to drill through.  Our previous example, the Oregon Columbia, has was designed without any pry points, meaning it does not have any room around the door or around the joints to insert a pry bar or other tool to pry it open.  The Euro lock used in the Columbia is not only difficult to pick, it is also quite difficult to drill which, combined with the structural design, makes this one of our most secure mailboxes.

Source: http://about.usps.com/publications/engineering-standards-specifications/spusps-std-7b01/welcome.html