enclosure blocks follow the pattern of the standard letter. Margins may be less than 1 inch. Short speedletters maybe penned. The text begins two lines below the reference line.

Paragraphs and subparagraphs are single spaced, with two lines between each division. When enclosures are sent with a speedletter, the enclosure line is prepared and positioned in the same manner as it is in the naval letter. The enclosures are numbered (1), (2), (3), etc., and described. Enclosures sent under separate cover are designated by (sep cover) typed between the number and the description.

Continuation pages are typed on plain bond paper following standard letter format for margins, page numbers, etc. Naval Message

A message is an official communication in brief form transmitted by electrical means through Navy telecommunication centers. A message is used for urgent communication where speed is of primary importance. Messages should not be used when the necessary information can reach its destination in time for proper action by letter or speedletter.

Naval messages are prepared on Department of Defense MESSAGEFORM 173 (DD 173). Messages must be typed on DD 173s using an OCR font with the character set for 10 pitch on the typewriter. Figure 2-12 shows the format of a naval message prepared on the DD 173 during a period of minimize.

Naval messages are prepared in accordance with the Naval Telecommunications Users Manual (NTP-3). The NTP-3 provides specific guidance on the preparation and transmission of naval messages. Changes to message preparation procedures occur frequently. You should use the latest revision to the NTP-3. If in doubt, check with your local communications office.

The text of a message also contains an SSIC. The SSIC consists of an appropriate five-number group, preceded by the letter N, taken from the latest edition of SECNAVINST 5210.11. The letter N means that the numeric group was taken from the Navy list. If the SSIC you are using only has four digits, precede the SSIC with a zero.

The SSIC appears only in the message text, and should be placed on the same line and immediately following the security classification and any special handling instructions included; for example, LIMDIS, NOFORN, etc. The SSIC begins and ends with a double slant sign; for example, UNCLAS //N02300//.

Abbreviations within the texts of messages should be limited to those meanings that are self- evident, unequivocal, or which are recognizable. In doubtful cases, clarity always takes precedence over brevity. Messages that are directives have additional identifications at the head of the text, which consists of the authorized abbreviation of the originating authority followed by the designation "INST" for an instruction or "NOTE" for a notice and the appropriate classification number.

Punctuation used in naval messages is limited to the following symbols:

Hyphen (-)

Dash (-)

Question mark (?)

Colon (:)

Dollar sign ($)

Apostrophe ()

Ampersand (&)

Parentheses (open and close)

Period (.)

Comma (,)

Semicolon (;)

Virgule (/)

Quotation mark ()

The following symbols, generally available on standard office typewriters, are not available on the Navy's teletypewriter keyboards and should not be used.

Number sign (#)

At sign (@)

Percent (%)

Fractions ( 1/4, 1/2)

Asterisk (*)

Underscore (_)

Cent sign (?)