from WWW to Nato Stock Number

Here is the English translation of a work about military delivery codes I have recently written for the Italian magazine "Orologi & Market" :

This subject would deserve by itself a medium-size book ,but I think is however interesting to share some basics informations, particularly referring to the military watches delivered to the UK forces on HMS.

In the short space of a single work it's impossible to describe every possible situation and all peculiar chances , so the owners of eventual "exceptions" are kindly asked to show them.

During the WW II and sometimes up to the second half of the '50 the most common codes were the followings :

1)ARMY ( that after Cromwell is not any more "Royal",a term that is on the contrary granted to single units which distinguished themselves by different ways , as bravery or loyalty ) :

--WWW =waterproof wrist watch, followed by a capital letter identifying the manufacturer ( for ex. K for Timor , Y for Omega , F for Longines );

--" broad arrow" ( a stylized arrow pin that indentifies the item as Crown property );
-- one or two series of digits that show the progressive assignement number and sometimes also the case number of the watch.

2) ROYAL AIR FORCE :
--abbreviation 6B ( or sometimes 6BB/6A/6E ) followed by a number ( usually 3 digits )identifying that particular model and his type; --year of delivery and progressive assignement number : about this point it's really important to emphasize that every new year the assignement number was not beginning with "1", but with the first free number , so for ex. if in 1945 the last number assigned was "6431" , in 1946 the first
assignement would have been "6432".
( this procedure has been continued up to the present days..... ).

Sometimes ( almost in watches delivered during WW II ) there was also the abbreviation "AM" that stands for Air Ministry.

3) ROYAL NAVY ( that includes also the Royal Marines and the Fleet Air Force ) :
--HS = Hydrographic Service ( and not Survey ! ), used also for watches delivered to the Royal Marines/other branches belonging to the Navy ), followed by a number ( from 1 to 11 ) defining type and/or destination , so for ex. "HS 9" is for a wrist-chronograph , "HS 10" is for divers'watches ,and so on; -besides the broad arrow there ia also a progressive number that can be either the case number or
the progressive assignement number.

All the abbreviations described above are not related at all with the Nato Stock Number.
Since the beginning of the '50 we can find backs with series of numbers often wrongly related to the NATO codification :

a) 0552 : called by someone < Nato prefix for UK Navy watches > , while this is an UK military code ( so choosen by the MOD = Ministry Of Defence ) that stands for a Royal Navy watch.

b) W 10 : that is for a UK Army watch ( this is also a MOD code ).
In the early '50 arrive new kinds of codes that we could define " hybrids",as they contain either parts of a national classification ( like those described above ) and parts of the Nato one.

A typical example of hybrid code can be seen in the Omega " fat arrow " ( so called for the big brad arrow printed on the dial ); in the back we in fact have :

i)6645 that is the Nato code for a wrist watch ( we shall find later in the NSN );

ii) 101000 that is the identifying code for this model ( later this code will have 7 digits );

iii) 6B that stands for RAF ;

iv) 542 that shows the type , as explained above ( in this case wrist watch for pilots );

v) progressive assignement number ( for ex. 6450 );

vi) year of delivery ( for ex. "53" ).

In watches for the Royal Navy ( for ex.an Hamilton chronograph )we have :

i) 0552 that stands for a RN watch ;

ii) 924-3306 that is the type code ( in this case a chronograph );

iii) progressive assignement number ( for ex. 1720 )

iv) year of delivery ( for. 72 ).

If the same model would have been given to the RAF we should have seen :

i) 6B ( RAF ) ;

ii ) 551 that is the type code used for the same model by RAF ;

iii ) delivery number and year of delivery ( for ex. 1860/72 ).

Sometimes the 7 digit type code will remain unchanged in the NSN ( as for Rolex subs delivered in
the '70 ), sometimes it will be different as we shall see.
The Nato Stock Number arrives in the second half of the '60 : it was studied to make a perfect identification within NATO of every kind of supplies ( from a bullet for rifles to a replacement for laundry machines ), in order to get an easy classification and supply of all items already in use or expected to be used in the military environment.

It's made of 13 digits so defined :
a) the first 4 digits are the SPECIES ( = sort ) code , in other words the "family" to which the item belongs ( for ex. 5305 = screws , 6645 = wrist watches..... ) ;

b) digits 5 and 6 are the code of the country who has given the present NSN , that can be well
different form the one who has made it ( and this explains why for ex. a watch produced in France could have the country code of another nation , like Germany or USA );
Some country codes are :

-- from 00 to 09 : United States
--99 for UK
--12 for Germany
--14 for France
--15 for Italy.

c) the last 7 digits ( from 7 to 13 ) are the own code of the item , so all 7 digit codes describe an item ( or a group of items with extremely close features ) within the nation who has given this particular NSN.

This means :
1) the 7 digits code ( part 3 of the NSN ) is defined as " with no inherent significance " , so it
does not give any information of the item classified ( in other words it's completely at random )

2) it's progressive ( it depends on the time in which the codification has been requested ) so for

ex. "545.778" can be a lamp ,and the following number an earth/air missile )
3) some 7 digits codes have been used by more than a country ( like for watches ) ,some only by the country who has created that code.

Some UK example are:
a)a Smith watch delivered to the Army in 1970 had :
W10-6645-99-961-4045 ( note that for Army watches there is still the W 10 prefix ),followed by the progressive number ( for ex. 15xx/70 );

b) Omega SM 300 and Submariners 5513/7 had the same NSN :

W10-6645-923-7697, obviously with different delivery numbers and years.
c) a watch for the Royal Navy still had an hybrid code :

0552-923-7697 followed by progressive number and year.
Up to the present days there is no proof that the progressive assignement number could start every year from a number lower than the higher given in the previous one.