The Cluster Box Units (CBU) 1/4" Steel Neighborhood Security Mailbox
Our Cluster Box Units (CBUs) are custom-built to meet the specific needs of each community and are designed as a long-term infrastructure solution — This is not a disposable product.
Fully welded ¼" steel frame construction
3/16" reinforced steel doors
No rivets, spot welds, or removable panels
Steel shell 3–4× thicker than standard CBUs
Recessed doors that eliminate pry points - VERY IMPORTANT!
Units weigh 250–550 lbs for true heavy-duty durability
Larger-than-standard tenant compartments - For less package space needed
Optional outgoing mail sections eliminate pry vulnerabilities commonly seen in traditional CBU designs - Ours are completely welded
We offer configurations from 8 to 14 tenant compartments per unit, with custom layout options including outgoing and package compartments as needed.
Our CBUs are built to help:
Deter mail theft & protect residents’ packages
Reduce long-term maintenance and replacement costs
Provide a secure, professional installation for your community
Important Note:
USPS approval is required for installation of their Arrow Lock. Our CBUs require both front and rear access — one side for the mail carrier and the other for tenants. Our CBUs exceeds postal requirements.
We would be happy to provide a detailed quote for your custom CBU project.
Please complete the “Get More Information” form by clicking the green button below. The form takes only a few minutes to complete and allows us to prepare options tailored specifically to your community.
If you prefer, you’re also welcome to contact us directly.
(800) 206-8067 or info@fortknoxmailbox.com
Thank you for considering Fort Knox Mailbox to protect your neighborhood’s mail and packages.
Hi Mike,
Our mailbox is fabulous!! We love it! All the neighbors sharing the mailbox were so impressed
by the sturdiness of it!
Thank your all your help! We just finished installing it this morning!
Debbie H.
Thank You for the message, the refund and well wishes for our trip. Likewise on our part in having the opportunity to meet you. All the neighbors are very happy with their investment and especially like the forest green color. I handed-off the last key this AM and it was great to see that a package, which would have not fit in our last mailbox, was waiting for them. The slot size is really convenient! Wish you continued success and know that the latest planting will germinate more business for Fort Knox from our area.
Take care !
T R
Shipment made it here and everything looks great. Installed the frame yesterday and waiting for the cement to set properly before installing boxes. I do have all the addresses and will send you them so you can get them back to me for installing. Had quite a crew helping with the installation and everybody is really impressed with the quality of the materials and production of the mail system. Also received the separate envelope with the keys.
Thanks,
Andy