How We Build The Best
4C Mailbox in the Industry...


Why We Are The Best!

Postal Products Unlimited is the first company approved by the U.S. Postal Service for manufacturing 4C Mailboxes! Reduce identity theft with the highest security mailbox on the market!

Made from a high strength and stainless steel, security and perfection is put first in these USPS approved 4C mailboxes. With the flush surface design and concealed hinges, tampering and prying open doors is close to impossible. Double-wall door design increases pull test capacity, while closer tolerances of each box reduces the size of pry points.


Secure 4C Mailbox
Protective Lock Rim
Protective Lock Rim to prevent twisting and torque on the lock
3-Point Lock Cam
3-Point Lock Cam secures the door in 4 places including the hinge side.
Smaller Carrier Access Door provides smaller pry points and increased overall strength
Smaller Carrier Access Door provides smaller pry points and increased overall strength.

Units feature a 3-point cam lock with protective lock rim; door secures in four places including hinge side. Each unit comes with an outgoing mail slot and carrier access door. Outgoing mail slot features a saw tooth guard to prevent mail from being fished out.






Design Elements

Double-Wall Door
Double-Wall Door design increases the pull test capacity on each door to 1500 lbs. of pressure.
Flush Surface Design
Flush Surface Design provides a smooth surface to prevent dirt and ice build-up, as well as eliminating leverage for prying.
Conceal Hinges
Concealed Hinges prevent tampering with the front loading master door to gain access to the entire unit.
Closer Tolerance
Closer Tolerance to reduce the size of pry points.
Sawtooth Guard
Saw tooth Guard on the outgoing mail slot helps prevent mail from being fished out.