LETTER & SERIAL NUMBERS

Starting in 1987 Rolex started putting a letter in front of its serial numbers. The following is a list of letter and the year the series was introduced. Please note that it is not uncommon to find a mix of serial numbers mixed in. What does this mean? Not much in terms of the watch itself other than the fact the the old serial number watches were/are less popular and they have had it sitting in their inventory for some time. This does not effect the factory warranty as it starts at the date of purchase and not the date of manufacturing.

R 1987
L 1988
E 1990
X 1991
N 1991 (Nov)
C 1992
S 1993
W 1994
T 1996
U 1997 (Aug)
A 1998 (Nov)
P 2000 (Jan)
K 2001 (Sep)
Y 2002 (Sep)
F 2003 (Sep)
D 2005 (Apr)
Z 2006 (May)
M 2007 (Aug)

HOLOGRAM ON CASE-BACK

Does this guarantee the watch is real?

Absolutely not, the counterfeiters have been putting on a hologram sticker on the back for years. The holograms can be purchased by the sheets on ebay so do not assume that because the watch has a sticker on the back that it is real.

Do I decrease the value of the watch by removing it?

Not at all, since over time the sticker will wear and become a sticky mess. Also like I said above fake stickers can be bought so people these days don't really care if the sticker is on the back.

SUPERLATIVE CHRONOMETER OFFICIALLY CERTIFIED

What this means is that the watch has been tested by Contrôle Officiel Suisse des Chronometers (COSC) COSC is the swiss standard for testing watch movements. They are independent and every movement gets tested with the same standards.

A movement that is COSC certified is accurate from -4 to +6 seconds a day anything in that range is acceptable. So if your watch is slow 4 seconds a day or fast 6 seconds a day (or anywhere in between) don't worry about it.

Something to note is of the China and HK codes. Rolex knows about the Chinese and their superstitions and have chosen numbers that represent good luck and wealth through a play on the way the words for certain numbers are pronounced in Chinese (8s = wealth, 2= ease, 3= for life, in other words some of these codes mean easy wealth or wealth for life) now one of the codes for HK is 400 which is sort of bad (4 in Chinese sounds like the word for die) but it is believed  this is because the number was issued back before Rolex realized how superstitious the Chinese are.

When were they Introduced?

1926 Oyster Case
1927 Serial Number On Oyster Case
1931 Oyster Perpetual
1938 Bubble Back
1938 Oyster Bracelet
1945 Jubilee Bracelet
1945 Date-just
1950 "Mercedes" Hands
1953 Submariner 100m/330ft
1953 Explorer
1954 GMT-Master
1954 Submariner 200m / 660ft
1954 Cyclops (aka Magnifying bump on Crystal)
1954 Lady's Oyster Perpetual
1956 Day-Date
1956 President Bracelet
1959 Submariner gets Crown Guards and 40mm Case
1960 Deep Sea Special
1961 Oyster Cosmo-graph
1962 Cosmo-graph Daytona
1965 Submariner Date
1965 Submariner Date 18 k YG
1967 Sea-Dweller
1971 Explorer II
1972 Hacking Movement
1974 Sapphire Crystal
1976 Oyster quartz
1977 Oyster quartz Day-Date
1977 Quick Set Date Feature
1978 Sea-Dweller 4000
1979 Submariner 300m/1000ft with Sapphire Crystal
1983 GMT-Master II
1983 Submariner Rolesor (aka Sub TT)
1988 Cosmo-graph Daytona (Zenith Movement aka Cal. 4030)
1992 Yacht-master
1994 Yacht-master Lady & Mid-Sized aka Boys Size
2000 Cosmo-graph Daytona with new in-house movement (Cal. 4130)
2001 Laser Etched Hologram In Crystal
2003 "Green" Submariner Date (aka Anniversary Model with Maxi Dial)
2002 end of Y series early 2003. Non lugs holes started to make their appearance on most models.
2004 Serial F/D on some models the Rolex On the Rehaut ring
2004 New Date-just Case
2005 New GMT-Master YG (Cal. 3186)
2006 New GMT-Master Rolesor (Cal. 3186)