The simple answer is nothing. CBUs, or cluster box units, are a product of the USPS, which licenses out manufacturing. Both manufacturers must produce the units with the same materials to the exact specifications, including the texture of the paint. The units are so similar that parts are interchangeable between the two manufacturers.

So, why is there a price difference between the Florence and Salsbury CBUs?
-Florence is the larger of the two manufacturers and is located in Manhattan, Kansas.
-Salsbury is located in Los Angeles, California. They have a 600,000-square-foot warehouse in the greater Los Angeles area.

The bottom line is that both manufacturers produce the same product using the same materials and have the same shipping lead times. If you order one CBU from each manufacturer, the only difference you will see is the price you pay for each unit.

The basic requirements for 4C mailboxes are as follows:

1. The post office MUST approve the location of where the mailboxes are installed. Always consult with your local post office before ordering or installing any mailboxes for your project.
2. No customer lock shall be over 67” from the finished floor. No mail slot shall be under 28” from the finished floor.
3. ONE parcel locker for every FIVE mail slots. This is where there is some grey area. The local post office has the final say on how many parcel lockers are required for any project within their delivery area. They can require a ratio of up to 1:5, but not more. They can also allow less, but that is left to their discretion.
4. At least one customer compartment shall be positioned at a height of less than 48” from the finished floor. However, local regulations may override this and require 100% of the mailboxes to be under 48” from the finished floor. Check your local building code for the regulations in your area.
5. No parcel locker compartment shall be under 15” from the finished floor. It is essential to contact your local post office during the planning stage of your project. Some post offices are more relaxed on these requirements than others and will allow exceptions to these rules.

To find the contact information for the post office in your area please use the following link: https://tools.usps.com/locations

Florence part numbers are arranged so that you can quickly determine the series and the number of mail slots each product has.

4C16D-20-BK

4C = The model

16 = How many rows high. This can be between 06 & 16. The larger the number the taller the unit will be.

D = Double wide (D) or single wide (S).

20 = How many mail slots the unit has.

BK = The color code. Sandstone (SD), Black (BK), Dark Bronze (DB), White (WH), Forest Green (FG), Silver Speck (SS), Gold Speck (GS), Antique Bronze (AB), Postal Grey (PG),

140075A

1400 = The model

7 = How many doors high. This can be 5 to 7 on the 1400 series

5 = How many doors wide. This can be 2 to 5 on the 1400 series

A = Color code. These units only come in anodized aluminium so this will always be A.

1600106A

1600 = The model. 1600's are front loading and 1700's are rear loading units. THESE UNITS ARE FOR PRIVATE DELIVERY ONLY. THE USPS WILL NOT DELIVER TO THESE UNITS.

10 = How many doors high. This can be 7 to 10 on the 1600 & 1700 series

6 = How many doors wide. This can be 2 to 6 on the 1600 & 1700 series

A = Color code. These units only come in anodized aluminium so this will always be A.

In this industry all orders ship directly from the manufacturer. Products are too large and too expensive to ship twice making it impossible to stock items and maintain a competitive price.

Both Florence and Salsbury do not accept rush orders. All orders are processed on a first come first serve basis. No dealer can get them faster or cheaper than anyone else.

If there is a specific style needed or a general concept desired, there are endless options available. Contact us and we will design something with you.

Installation is available for Northern & Central Illinois. Availability is between 5-7 business days from the day of request. Installations are done year round, weather permitting. Payment is required at time of request.

Orders can be cancelled/refunded prior to shipment excluding custom orders. 1-year limited warranty. 60 day return policy.

The customer is responsible for return shipping and 20% restocking fee. Excludes custom orders.

Please ship items to: 
U.S. Post Company
2004 W Lincoln Rd
Lakemoor, IL 60051

Liftgate delivery service involves a truck affixed with a piece of hydraulic or electric equipment that is installed on the back of a truck, enabling freight to be lifted several feet off the ground to the tailgate of the truck, or lowered from the truck’s tailgate to the ground.