Get a reliable, durable unit you can rely on when you shop with us. This 4C mailbox is manufactured from heavy gauge aluminum and has a corrosion resistant finish to help it resist weather and scratching. All of this means this unit is perfect for both indoor and outdoor use (with kiosk or other application, pending local USPS approval). This mailbox is great in terms of security. The double locking parcel door mechanism keeps packages safe while the other doors are outfitted with USPS-1172 910A locks. It meets USPS requirements of one parcel locker per ten tenant compartments, and STD-4C requirements for new construction and renovations. This long-lasting mailbox is a great choice for your commercial building, school, apartment, and more. Please contact us for specific unit measurements.