I suppose if the local postmaster wanted to, he could have a say about 1/4" plate mailboxes
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2.0 Curbside Mailboxes
2.1Manufacturer Specifications
Manufacturers of all mailboxes designed and made to be erected at the edge of a roadway or curbside of a street and to be served by a carrier from a vehicle on any city route, rural route, or highway contract route must obtain approval of their products under USPS Standard 7, Mailboxes, City and Rural Curbside. To receive these construction standards and drawings or other information about the manufacture of curbside mailboxes, write to USPS Engineering (see G043 for address).
2.2Custom-Built
Mailbox
The local postmaster may approve a curbside mailbox constructed by a customer who, for aesthetic or other reasons, does not want to use an approved manufactured box. The custom-built box must generally meet the same standards as approved manufactured boxes for flag, size, strength, and quality of construction.
2.3Address Identification
Every curbside mailbox must bear the following address information:
a. A box number, if used, inscribed in contrasting color in neat letters and numerals at least 1 inch high on the side of the box visible to the carrier’s regular approach, or on the door if boxes are grouped.
b. A house number if street names and house numbers have been assigned by local authorities, and the postmaster authorizes their use as a postal address. If the box is on a different street from the customer’s residence, the street name and house number must be inscribed on the box.
2.4Owner’s Name
The mailbox may bear the owner’s name.
2.5Advertising
Any advertising on a mailbox or its support is prohibited.
2.6Mailbox Post
The post or other support for a curbside mailbox must be neat and of adequate strength and size. The post may not represent effigies or caricatures that tend to disparage or ridicule any person. The box may be attached to a fixed or movable arm.
2.7Location
Subject to state laws and regulations, a curbside mailbox must be placed to allow safe and convenient delivery by carriers without leaving their vehicles. The box must be on the right-hand side of the road in the direction of travel of the carriers on any new rural route or highway contract route, in all cases where traffic conditions are dangerous for the carriers to drive to the left to reach the box, or where their doing so would violate traffic laws and regulations.<!-/quote-!><hr size=0></blockquote>
