44 070 listings including promoted listings
Omega Constellation
198.0034
R11 000
Excl. shipping
Private Seller
Rolex Explorer II
16570
R147 700
Excl. shipping
Private Seller
Popular
Rolex Datejust 41
126334
R265 000
Excl. shipping
Private Seller
Popular
Omega Seamaster Diver 300 M
22545000
R56 029
Excl. shipping
Private Seller
Popular
Breitling Superocean GMT
Automatic White Dial Men's Watch A32380A9-A737
R34 472
Excl. shipping
Private Seller
Promoted
Audemars Piguet Royal Oak Offshore Chronograph
NEW ROYAL OAK OFFSHORE ROSE PINK GOLD IN RARE COLLECTORS SET
R1 259 064
Excl. shipping
Private Seller
Popular
Citizen
Bullhead AN3660-81A Chronograph
R4 453
Excl. shipping
Private Seller
Popular
Tudor Black Bay 36
M79640-0002
R56 419
Excl. shipping
Private Seller
Popular
Omega Seamaster Diver 300 M
2254.50
R48 914
Excl. shipping
Private Seller
Popular
Omega Seamaster Diver 300 M
2551.80.00
R39 557
Excl. shipping
Private Seller
Zenith El Primero
A781
R105 097
Excl. shipping
Private Seller
Promoted
Rolex Submariner Date
41mm Stainless Steel Black Dial - Ceramic Bezel (126610LN)
R288 078
+ R1 845 for shipping
Popular
Ulysse Nardin Diver Chronometer
263-10-3/92
R91 305
Excl. shipping
Private Seller
Popular
Omega Seamaster Planet Ocean
600M Co-Axial Chronometer 37.5 mm
R67 976
Excl. shipping
Private Seller
Popular
Omega Seamaster Aqua Terra
(Co-axial) Serviced 06/2024
R62 896
Excl. shipping
Private Seller
Popular
Omega Speedmaster Broad Arrow
3551.50.00 (Overhauled)
R62 318
Excl. shipping
Private Seller
Breitling Navitimer World
A24322
R93 076
Excl. shipping
Private Seller
Promoted
Patek Philippe Calatrava
chronometer ref 3483
R582 708
Excl. shipping
Private Seller
Vostok
Precision 2809
R3 056
Excl. shipping
Private Seller
Popular
Zenith El Primero Chronomaster
Triple Date 010240410 Moonphase 40mm Automatic
R53 479
Excl. shipping
Private Seller
Rolex Datejust 41
126334
R204 971
Free shipping
Omega Constellation
Stainless Steel yr.1966
R15 999
+ R259 for shipping
Popular
Chopard Alpine Eagle
<Aletsch Blue>
R155 592
Excl. shipping
Private Seller
Promoted
Rolex Datejust 41
18k White Gold & Steel Grey Slate Wimbledon Green Roman Dial Jubilee 126334
R288 450
+ R1 845 for shipping
Popular
Rolex Submariner (No Date)
124060
R213 928
Excl. shipping
Private Seller
Popular
Omega Constellation Double Eagle
Co-Axial Chronograph
R40 063
Excl. shipping
Private Seller
Popular
Omega Seamaster 300
233.32.41.21.01.001
R142 600
Excl. shipping
Private Seller
Rolex Oyster Perpetual
2940
R55 750
Excl. shipping
Private Seller
Popular
Rolex Datejust 41
126334 Rhodium _ Full Set From 07/2017 _ Like New
R240 415
+ R3 647 for shipping
Promoted
Rolex Datejust 41
Oyster 41 mm Oystersteel Mint Green Dial Fluted Bezel Jubilee Bracelet Ref 126334
R316 774
+ R1 845 for shipping

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Rolex GMT-Master II
126720VTNR Full Set 2024
R365 716
+ R6 112 for shipping
Rolex Sea-Dweller
126600
R275 779
Free shipping
Breitling Aerospace EVO
E7936310/BC27/152E
R46 584
Excl. shipping
Private Seller
Popular
Omega Seamaster Diver 300 M
Nekton Edition
R76 380
Excl. shipping
Private Seller
Omega Constellation
ref.2852-16C SERVICED
R34 999
+ R259 for shipping
Promoted
Omega Speedmaster
Gold 18kt - Full Set - FULL SERVICE 06/24 - Original Omega Strap/Buckle
R132 432
+ R4 666 for shipping
Popular
Omega Speedmaster
1957 Trilogy 60th Anniversary Limited Edition
R140 725
Excl. shipping
Private Seller
Popular
Omega Speedmaster
Dark Side of The Moon
R139 753
Excl. shipping
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Tudor Black Bay Fifty-Eight
M79030B-0001
R66 900
Excl. shipping
Private Seller
Popular
Omega Seamaster Diver 300 M
210.22.42.20.01.001
R80 125
Excl. shipping
Private Seller
Popular
Breitling Navitimer GMT
AB044121/BD24/441X/A20BA.1
R73 603
Excl. shipping
Private Seller
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Porsche Design Chronotimer
6010.1.03.004.05.2
R91 684
Excl. shipping
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Omega De Ville Prestige
424.13.40.20.02.001
R41 372
Excl. shipping
Private Seller
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Omega Constellation
F300hz
R7 454
Excl. shipping
Private Seller
Tudor Pelagos
FXD MN 2021
R74 069
Excl. shipping
Private Seller
Seiko Chronograph
7T92-0DW0
R4 099
Excl. shipping
Private Seller
Rolex Submariner Date
126610LN
R279 506
Free shipping
Promoted
Rolex Submariner (No Date)
Black Dial No Date 124060
R250 624
+ R1 845 for shipping
Hoffman Racing 40 - All Black - Chronograph
R3 913
Excl. shipping
Private Seller
Breitling Navitimer World
A2432212/B726
R102 392
Excl. shipping
Private Seller
Popular
TAG Heuer Formula 1 Quartz
CA1211
R13 006
Excl. shipping
Private Seller
Rolex GMT-Master II
aka the "Sprite" | 2023
R348 411
+ R12 140 for shipping
Rolex GMT-Master II
"Sprite" Oyster NEW 2022
R356 527
+ R5 501 for shipping
Promoted
Porsche Design Flat Six
P6310
R25 468
Excl. shipping
Private Seller
Breitling
Premier B01
R73 969
Excl. shipping
Private Seller
Popular
TAG Heuer Carrera Calibre 16
CBM2112.FC6455
R52 965
Excl. shipping
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Seiko
DX 25 Jewels 6106 - 8600T
R5 497
Excl. shipping
Private Seller
Omega Constellation
TV Shape Automatic Chronometer 166058
R14 888
Excl. shipping
Private Seller
Popular
Rolex Datejust 41
126334
R248 230
Excl. shipping
Private Seller
Promoted
Rolex Submariner Date
16610 military NATO 1994 S series
R713 095
+ R12 224 for shipping
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Chronometer - Certified Precision

"Chronometer" may sound like a fancy name for a normal watch - after all, it just comes from the Greek words for "time" and "measure" - but chronometers are really something quite special. Chronometers are watches, yes, but watches that have been tried and tested and certified to meet exacting precision standards. The COSC in Switzerland determines which watches may actually call themselves "chronometers".


The Oceanic Origins of Chronometers

Though the Swiss set the standard, the English coined the word. In the quest to calculate the longitude, the Englishman Jeremy Thacker, a clockmaker of extraordinary skill, created a series of increasingly accurate clocks, well beyond what had had previously been achieved. The clocks were intended to be used aboard ships and had to keep absolutely accurate time in order to allow for calculating longitude precisely, and thus fixing the position of the ship in the vast ocean. The last of Thacker's chronometers was actually more like a very large pocket watch.

Other clockmakers - and increasingly watchmakers - copied from and improved upon Thacker's final chronometer, producing watches of greater and greater precision. The original standards for accuracy were actually far more exacting than those currently maintained by the COSC in Switzerland, so very few watches were certified as chronometers and thus very few were actually produced and sold. The original chronometer requirements for mechanical watches are no longer necessary, since digital watches can already exceed them, but chronometers are still manufactured and sold (and resold) today as examples of extremely fine precision engineering. The use of jewels and precious metals in watches owes its origins to chronometers - these materials were used to make the mechanical movements as precise as possible.


Officially Certified Chronometers

Chronometers are no longer rare. More than a million Officially Certified Chronometer certificates are issued each year. Those watches that pass the most rigorous of the COSG's tests are rewarded with a special serial number and, indeed, the right to call themselves "chronometers" at all. Chronometers must meet several requirements: they must display the seconds; they must be highly precise; they must demonstrate that precision over the course of several consecutive days of testing; they must perform precisely in different positions and at different temperatures.


Chronometers in Everyday Use

This may sound extreme, but such reliability was crucial for individuals and groups that had to rely on the precision of portable mechanical timekeepers in the past. Pilots watches, for instance, needed to perform as chronometers (and those that did not had to be hackable). The famous B-Uhren, commissioned by the German Luftwaffe and manufactured by several companies, were chronometer-certified pilots watches - or chronometers that were used as pilots watches, depending on your perspective. Interestingly, despite the many years between Thacker's invention and the production of the B-Uhren, chronometers were still tightly bound to use in navigation.

First at sea, then in the air. And, still today, at sea again - or at least under it. Some diving watches, like the Rolex submariner, are also certified chronometers. Divers must be able to reliably track how long they've been under and how much time they have to surface.

Though their accuracy may have been eclipsed by digital watches, chronometers are still useful today.