COMDTINST 5216.4E
6. Envelopes and Mailers. Use envelopes or mailers slightly larger than the material being
mailed and of sufficient strength to protect the contents during mail handling and
delivery. Use number 10 standard letter size envelopes whenever possible. With a size
of 4 ½ x 9 ½ inches, a standard paper size 8 ½ x 11 inches may be folded in thirds.
Generally, documents with four or less pages should be folded and mailed in a letter size
envelope. To qualify as First-Class Mail®, envelopes must be at least 3 ½ inches by 5
inches (3 ½ inches by 5 ½ inches for international), and no larger than 6 ⅛ inches by 11
½ inches and less than ¼ inch in thickness. Use large envelopes for mailings that cannot
be folded (i.e., photographs, certificates, negatives, and bulk material, etc.). Note that
envelopes larger than 12 inches by 15 inches exceed the flat rate and the cost is
significantly higher.
7. Mailing and Stewardship. Consolidate outgoing mail whenever possible and avoid
excessive packaging. All mail generated on the same day and destined for the same
unit/location shall be placed together inside an appropriate mailer such as a large
envelope or flat rate box and sent via USPS or commercial carrier (FedEx/UPS, etc.)
endorsed “Consolidated Mail.” The receiving mailroom will open and sort the contents
for unit/location delivery.
8. Internal Mail. An official U.S. Government messenger envelope (Optional Form 65B) is
used to send mail and packages between offices/units located within the same
geographical area, building, and/or base through a centralized mail center. Enter the
appropriate address including a suite, room, STOP, or office number, if available.
Appropriate mailing label standards remain the same for the contents. Those who have a
Standard Workstation account must keep their current location and status updated on the
Global Address List (GAL) to avoid misrouting. Check with your local mailroom for
options on this service, often referred to as guard mail.
9. Forms of Address, Salutation, and Complimentary Close on Letters. The DHS Executive
Correspondence Handbook (series) style and usage guidelines provide some examples of
models of address and salutation. Appendix B of this Instruction provides examples of
Coast Guard models of address and salutation. A comprehensive source for DoD models
of address is found in the United States Air Force Handbook AFH33-337, titled Tongue
and Quill which is found at the Air Force E-Publishing website e-publishing.af.mil/ and
in Appendix A. The Coast Guard style preference is to spell out military models of
address fully, such as Dear Commander Lee, or Dear Petty Officer Gonzalez. For
civilians if a title is not known, then using Mr., Ms., or Mx. such as Dear Mr. Nguyen,
Dear Ms. Williams, or Dear Mx. Smith should be used. Mx. is the most accepted gender-
neutral title and should be used if a preference is unknown. If a title is known, the title
should be used, for example Dear Mr. Ambassador Kim, or Dear Dr. Crawford. If a
person specifically refers to themselves as Mrs., this may be used, otherwise the
preference is Ms. To address girls under the age of 12 use Ms. or Miss, and to address
boys under the age of 12, use Mr. If the name or gender is unknown, use a professional
or organizational title, such as Dear Director of Health and Safety. If it is known that the
recipient does not prefer any of these titles, begin the greeting by using the individual’s
first name, middle initial, and last name (i.e., Dear Calypso N. Seabrook).
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