This high quality 4C mailbox has 4 tenant compartments plus an outgoing mail compartment. You can rest assured that all your mail will remain safe, as each door is secured with a new USPS-1172 910A lock (plus three keys per lock). This durable unit is sure to last for many years, as it is constructed from heavy gauge aluminum with a corrosion resistant finish. With a finish designed to resist weather and prevent scratching, you get a mailbox that can be used both indoors and out (with kiosk or other application, pending local USPS approval). It meets USPS requirements for new construction and renovations. Invest in a high quality mailbox for your apartment, commercial building, and more! Please contact us for specific unit measurements.