background image

U.S.P.S. APPROVED 

 

With its high-security design and quality construction, Salsbury’s 3700 series USPS approved 4C horizontal mailboxes will provide years of 

maintenance free service.  These units meet all the requirements of USPS-STD-4C, the new high-security standard developed by the United 

States Postal Service. 

 
 

Typical Installation 

 

 

 

Preparatory Steps 

 

1.  Have mailboxes and instructions on hand before starting wall 

construction. 

2.  Unpack and review contents of shipping cartons. 

3.  Gather tenant and parcel locker keys and store in a secure place. 
4.  
Read installation instructions document thoroughly. 

5.  Determine rough opening size(s). 

6.  Determine rough opening location above finished floor. 

7.  Determine framing configuration and location. 
8.  Procure materials for wall construction. 

 
 

Rough Opening Dimensions 

 

Each unit requires a separate opening in the drywall.  Each pair of 

units will have a 2x4 stud separating them.  The trim frames cannot 

be butted together.  There will be a space between edges of trim  

frames of approximately ¾” when 2x4 studs with drywall separate the 
mailboxes. 

 

Calculation Of Space Required for Multiple Units 

 

For overall width of mailbox installation, add all of the stud spacings 
and subtract ¾”.  For overall height of units, see the dimension chart 

below.

 

 
 
 
 
 

Wall Construction 

 

Particular attention must be paid to wall framing to provide a strong 

and secure attachment of the mailbox units.  Stud spacing must be 

accurate to ensure that there is minimum space between the studs 
and the mailbox frame and minimum mailbox frame distortion when 

the fasteners are tightened between the frame and the studs.  Studs 

must be installed plumb and square to further ensure proper fit of the 

mailboxes. 

 
 
 
 

Dimensions – FRONT LOADING 

WIDTHS 

1 COLUMN 

2 COLUMN 

Overall 16-3/8” 31-1/8” 

Rough Opening 

15-5/8” 

30-3/8” 

Stud Spacing 

17-1/8” 

31-7/8” 

 
 

HEIGHTS OVERALL 

ROUGH 

OPENING 

Maximum Height 

56-3/4” 

56” 

15 Doors High 

55” 

54-1/4” 

13 Doors High 

48” 

47-1/4” 

11 Doors High 

41” 

40-1/4” 

9 Doors High 

34” 

33-1/4” 

7 Doors High 

27” 

26-1/4” 

5 Doors High 

20” 

19-1/4” 

3 Doors High 

13” 

12-1/4” 

 
 

                

4C Horizontal Mailboxes - 3700 Series 

FRONT LOADING Installation Instructions

 

SALSBURY INDUSTRIES

 

1010 East 62

nd

 Street, Los Angeles, CA 90001-1598 

                                                     Ph: 1-800-624-5269              Int’l Ph: 323-846-6700 
                                                     Fx: 1-800-624-5299              Int’l Fx:

  

323-846-6800 

                                                    www.mailboxes.com              [email protected]

 

Installation instructions are provided as general guidelines. It is advised that a professional installer be consulted. Salsbury Industries assumes no product assembly or installation liability

Copyright © 2008 Salsbury Industries.  All rights reserved.  (P/N 370137, Rev. 15, 10/29/2008)  Page 1 of 4 

 

Reviews: