WatchUSeek Watch Forums banner

1 - 9 of 9 Posts

·
Registered
Joined
·
678 Posts
Discussion Starter #1
http://quartzimodo.com/articles/the-seiko-kinetic-boon-or-bane/comment-page-1/
The Seiko Kinetic. Now that’s a watch technology that had initially discouraged and mystified me for some time. When I first inquired about Seiko Kinetics at a small watch dealer, I was advised to stay away from Kinetics as far as possible. He mentioned about frequent customer complaints and warranty claims from his fellow watch sellers. "Stick to quartz or automatic", he advised. "A Kinetic will give you a headache later on".


What did he mean by that? The dealer didn’t elaborate the heart of the issue or the specifics. So I decided to turn to the Internet and do some research of my own. I learned about the internals of a Kinetic watch, how the movement worked and Seiko’s philosophy behind it.

Someday, all watches will be made this way!
"Someday, all watches will be made this way". That tag line had been Seiko’s timeless slogan since they first pushed quartz analog watches into the world in the late seventies. Seiko’s highly supercharged and persuasive ads bloomed in magazines and newspaper ads everywhere in full support for their revolutionary hybrid watch technology. Surely, Japan’s biggest watch making company couldn’t be wrong with the Kinetic?
Anyway, a half hour’s searching on the Internet gave me some indefinite and inconclusive information. One interesting website detailed the writer’s beef with Seiko. He was a mechanical engineer and bitterly complained of the geartrain backlash that affected his Kinetic watch’s minute hand. It had too much free play in it and would shift when the watch was tilted from side to side.
More worrying to me was the mention of multiple incidences of premature failures of capacitors in Seiko Kinetics, which was also reported by other Kinetic owners in his page here. The capacitor was integral to Seiko’s concept of a "battery-less" quartz watch. The company calls it the "energy storage unit" and what it basically does is to store electricity generated through wrist motion.



A closeup of the Seiko 5M42 movement, showing its coil block, oscillating weight and the capacitor (borrowed photo).​


The capacitor (or condenser) is fundamentally an electronic device with two electrodes which are separated by a dielectric insulator. It can store energy when it is charged and will release energy when discharged.
Seiko used two types of capacitors for its early Kinetics and A.G.S/Auto Quartz (pre-Kinetic) models. The earlier type was outsourced from the established Japanese electronics giant, Matsushita Electric, which is now known as Panasonic.
This capacitor was the model EECW2R4E334, which was the energy storage unit for early Kinetic calibers such as the 5M2x series. It was primarily designed to be used in confined spaces (like a watch module) where miniature primary lithium cells were specified. The EECW2R4E334 incorporated gold (the precious metal) as one of its raw components and is rated for 2.4V volts DC. It has since been discontinued by Panasonic.
Later Seiko developed its own capacitors and used them to replace the ones from Matsushita. The capacitors were made by Seiko’s sub-division called Seiko Instruments Incorporated (SII) and were designated the SL920.



A photo of the new TC920S LiOn cell (left) and the old SL920 capacitor (right). Pic courtesy of Poor Man’s Watch Forum


The tiny capacitors were supposed to last for at least several years but apparently they didn’t. Many batches leaked while in use, which resulted in dead Kinetics and many dissatisfied customers. It became somewhat a widespread problem which could have hurt sales of Kinetic models worldwide.
A Kinetic watch is directly powered by its energy storage cell and without it, the watch would simply stop working. The storage cell acts as a reservoir or buffer to store electricity generated by the electrical generating unit. The equivalent of the storage unit in a mechanical watch is the main spring.
I have no idea if Seiko’s engineers ever performed simulated accelerated aging tests of the capacitors. The designers spent a lot of time into perfecting the Kinetic’s micro electricity generator (they did a terrific job on it) but perhaps overlooked the long term reliability of the capacitor itself, which is a key component of the Kinetic architecture.



Issues with the early Seiko Kinetic watches

I decided to revisit the issues which had plagued me for more than a year. The majority of the complaints centered on the premature failure of the capacitors that Seiko used. They tended to leak and resulted in the watch being unable to run for than several hours before stopping.
I wondered if I would be risking my hard earned cash if I were to buy a Seiko Kinetic. Should I or shouldn’t I? After all, I had more than a dozen quartz and automatic Seikos at the time. Maybe I ought to try just one Kinetic for size and if things didn’t work well, I could sell it later.
Was the capacitor trouble widespread or was it just limited to certain Seiko Kinetic models or calibers? I later learned that the problem largely affected the early Kinetic calibers, particularly the 5M4x and 5M2x series. These were mostly movements that were made prior to the year 2000.
At the same time, Seiko had quietly rectified the capacitor leakage problem when they introduced the new 5M6x caliber, which is still in existence at the time of writing. In place of the capacitor, Seiko decided to use a rechargeable titanium lithium ion cell (LiOn) as replacement.
Rather than spend money to self-manufacture the LiOn cells, Seiko chose to outsource them from Maxell Corp, a renowned Japanese battery and computer media manufacturer. Maxell also makes disposable watch batteries and they probably had the best designed LiOn cells around.
The good news is that Seiko also discontinued using the problematic capacitors for its Kinetic models from 2000 onwards. Models that use the older calibers like the 5M2x and 5M4x series are able to be retrofitted with the LiOn cells without problems.
The LiOn cell that Seiko uses in its modern Kinetics is the Maxell TC920S, as pictured below. It is rated to give a potential difference of 2.2 volts DC at full charge.



http://quartzimodo.com/wp-content/uploads/2008/05/maxell-lion-cell-medium.jpg

Technically, the LiOn is a secondary battery which can be recharged and discharged repeatedly.
It does not operate on the principle of the capacitor but runs like the rechargeable battery that powers your cellphone, iPod, laptop or digital camera. Some people refer the LiOn cell as a "capacitor". From a technical point of view, this is incorrect. A capacitor and a rechargeable battery are constructed differently.
Going with Seiko’s long-running and expensive "battery-less watch" marketing campaign, the company prefers not to use the term "battery" when referring to the LiOn cell. I presume after the millions the company had spent on promoting the Kinetic as a watch that required no batteries, they probably didn’t want the public to get confused.
Probably someone in marketing came up with a brilliant idea and thus the technical sounding name Kinetic Electricity Storage Unit (or Kinetic E.S.U. for short) was born. Kinetic E.S.U. can refer to the old style capacitor or the newer LiOn rechargeable cell.


Advantages of the Lithium Ion rechargeable cell

Seiko’s decision to equip their Kinetic movements starting from the 5M6x caliber onwards with the lithium ion cell (and ditching the old capacitor storage unit) was a wise one.
Not only the LiOn cells were more reliable than the capacitor, they offered a much larger power holding capacity. This is capacity is also called the "power reserve". Depending on the caliber, the Maxell LiOn cells have a power reserve ranging from 1 month (for the 9T82 chronograph) to a whopping 4 years (for the 5J-series).
The typical reserve for a 5M-caliber Kinetic is up to six months and five months for a 7L22 Kinetic chronograph, fully charged. The 9T82 Kinetic consumes a lot of power when its chronograph is used (it has a 1/10sec stopwatch) hence its average reserve is just a month.
The 5J-caliber’s ability to keep time up to four years is due to its special Auto Relay technology. It has a unique power conservation (sleep mode) feature that shuts down the watch movement (except for the internal timing) when it hasn’t been worn continuously for 72 hours and longer.
When you pick up a Kinetic Auto Relay watch and shake it, its main time hands will magically spin to match the current time. The date calendar unfortunately has to be set manually, presumably due to the amount of power needed to spin those hands to catch up to the current date.
Seiko claims that their Auto Relay Kinetics can hold a charge for up to 4 years and I wonder if any Auto Relay owner has actually put this claim to the test.

[URL="http://quartzimodo.com/wp-content/uploads/2008/05/sng043p2.jpg"]

Two Seiko Kinetic Auto Relays: A recent Arctura SNG043P (left) and an earlier SMA113P (right)​

As far as I know, rechargeable lithium ion batteries have a self-discharge nature whereby its power will slowly deplete even though it’s not connected to any electrical load. Anyway, I don’t own an Auto Relay as I never liked their designs. Seiko Auto Relay Kinetics tend to be blingy and dressy, not really my kind of watch.



Drawbacks of the LiOn cell

On the flip side, having a very large power reserve also means that a lot of wrist motion is required to charge the LiOn cell to its fullest capacity. The original capacitors in the early Kinetic watches had a rather small storage and it needed about only 800 swings of the watch to charge it to its maximum reserve of 3 days. This reserve is still longer than the average mechanical movement’s reserve between 30 to 55 hours.
The Maxell LiOn cell with its maximum 6-month reserve on the other hand, requires at least 24,000 swings of the watch to get it to its full charge! Which means to achieve this, you have to wear the watch as frequently as possible. Alternatively, you could invest in a special charger such as a Seiko Energy Supplier.


A Seiko YT02A Kinetic charger. It can charge a 5M-caliber watch in 3 1/2 hours from a fully discharged state​

The Energy Supplier works on the principle of electromagnetic induction, like those home induction cookers and has no moving parts. For those of you technically inclined, you may want to read up on Faraday’s Law.

Some people have attempted to "charge" their Kinetics using watch winders meant for automatic timepieces. I’m not sure how efficient using mechanical winders would be as Kinetic watches literally need thousands of swings to get them to full charge.
These chargers are largely supplied to Seiko repair centers and to small numbers of authorized Seiko watch dealers. Perhaps the most well-known Kinetic charger is the model YT02A, which can be sourced from a few eBay sellers and online watch dealers. The YT02A can handle a variety of Kinetic calibers, including the current 5J22 Auto Relay and 7L22 Kinetic Chronograph models.
Whether it’s viable to purchase one of these YT02A chargers depends on how many Kinetic watches you own and how often you wear them. In my opinion, if you have over three Kinetics and seldom wear them, you might want to get one of these chargers.



File photo of my SMY003P Kinetic being charged on a Seiko Kinetic Energy Supplier unit at my watchmaker’s. This pyramid-shaped charger is different than the YT02A model (right).​

Unfortunately, the LiOn cell doesn’t have an infinite life span. Sooner or later your rechargeable cell will lose its ability to maintain an optimal charge. If you wear a Kinetic every day you probably won’t notice the efficiency loss until the LiOn cell is nearing its end. With models that aren’t equipped with the power reserve indicator feature, you won’t know this until the cell’s voltage drops to the point that your watch’s second hand starts ticking in an erratic manner.
Note that all rechargeable lithium ion batteries have self-discharge properties. They will slowly lose their power even when not in use. LiOn batteries are best kept at around a 40% charge capacity if you intend to store them for long periods without use.
Allowing a LiOn cell to discharge completely is also a total no-no. Doing so will seriously degrade the cell’s internal chemicals and reduce its ability to hold a charge. Be sure never to allow your Kinetic watch (or a solar powered one, such as Citizen Eco Drive or Casio Tough Solar) to stop functioning.
Also, be wary of buying a Kinetic watch at a store that has stopped for some time. Chances are if the watch has been in the store for many months or years, you’ll need to replace the KESU not long after you’ve bought it. Unlike solar powered watches that are continually charged so long as there is enough light, Kinetics need to be shaken often to keep them charged.
Many brick-and-mortar watch dealers couldn’t be bothered with this (the task itself is daunting if they have lots of Kinetics) and they allow the watches to self discharge over time.


Replacing the Kinetic ESU

It’s very important that you replace your Kinetic’s ESU at a Seiko service center or at least, at a jeweler that has experience in replacing Kinetic capacitors and LiOn cells.
I’ve heard a few horror stories of owners who unwittingly had their Kinetic ESUs replaced with primary silver oxide batteries! These usually happened at watch stores whose sales assistants are totally clueless about Kinetic watches and rechargeable cells.
Never substitute your Kinetic’s ESU with a silver oxide cell meant for quartz watches! Silver oxide cells are primary cells, not secondary cells. It’s possible for a silver oxide cell to leak or even burst if it is recharged. It’s just like those disposable alkaline batteries - they are not meant to be recharged with a reverse current.


A typical 1.55v silver oxide cell meant for quartz watches, which can damage your Kinetic movement if used instead!​

As the Seiko Kinetic is more of a quartz watch rather than a mechanical one, when it’s time for a service or repair, it’s best to take it to a Seiko repair facility. This is because the only major moving parts in a Kinetic are the oscillating weight and the micro step-up gears. The rest the components in a modular form, similar to a quartz watch.
However, if you are up to the task of replacing your dead KESU yourself, check out this excellent DIY tutorial by Reto Castellazzi. Reto is a well-known, veteran watch collector/enthusiast/seller and has quite a few hard-to-find Seiko watches for sale in his web site from time to time.


Buy a fresh replacement Kinetic ESU!

I thought it’s worth mentioning that if you’re replacing your failing rechargeable Lithium Ion cell, be sure that you’re getting a recently manufactured one. You’ll have to trust the seller or your watchmaker on this.
The reason for choosing a fresh rechargeable LiOn cell is because all Lithium Ion batteries start degrading when they leave the factory. Unlike disposable alkaline batteries that have very long shelf lives (about five years), a replacement LiOn cell that was made several years ago would have aged (and very likely in a state of total discharge). Therefore, they may not hold a 100% charge like when they were new.
This tip also applies to rechargeable LiOn and Nickel Metal Hydride (NiMH) batteries for consumer electronics like digital cameras, laptops, iPods, MP3 players, cellphones and the like.
So if you’re replacing your Kinetic watch’s KESU, try to ensure that you’re getting one from a recent batch.


Seiko Kinetic Calibers

The following is a table of Seiko Kinetic movement types which I have compiled from various sources. This list may not be exhaustive, so if you know of a Kinetic caliber not listed here, feel free to inform me.


CaliberDefault Kinetic ESU typeMax power reserveFeatures/CommentsProduction status1M20Capacitor72 hours (3 days), 3 months with LiOn cellDiscontinued3M21, 3M22, 3M62Capacitor168 hours (1 week)Power reserve indicatorDiscontinued4M21, 4M71Capacitor72 hours (3 days)Discontinued5D22, 5D44LiOn cell1 month Direct Drive, real time power reserve indicatorIn production5J21, 5J22, 5J32LiOn cell4 yearsAuto RelayIn production 5M22, 5M23, 5M25Capacitor72 hours (3 days)Power reserve indicatorDiscontinued5M42, 5M43, 5M45Capacitor168 hours (1 week)Power reserve indicatorDiscontinued5M62, 5M63, 5M65LiOn cell6 months Power reserve indicatorIn production
7D46, 7D48LiOn cell4 years Auto Relay, Perpetual CalendarIn production 7L22LiOn cell5 months1/5sec mechanical operated chronograph

In production 7M12, 7M22Capacitor72 hours (3 days) Discontinued7M42, 7M45Capacitor72 hours (3 days) Discontinued9T82LiOn cell1 month1/10sec mechanical operated chronograph

Possibly discontinuedYT47Capacitor72 hours (3 days)Produced for non-Seiko Japanese brands, e.g. Alba, GSX, etcDiscontinuedYT57, YT58LiOn cell6 months

Produced for non-Seiko, Japanese brands, e.g. Alba, GSX, etc

In production



My personal experience with Kinetics

I finally pulled the proverbial trigger on a Seiko Kinetic late 2004 after weighing the pros and cons of owning one. There were many models to choose from and I settled for the SKA013P since it had the classic diver-like styling and a radiant, jet black dial with framed rectangular indices.
What I liked about the Kinetic is the sensation of the oscillating weight spinning when I shake my arm. It almost feels like an automatic. Notice that I said "almost".
Compared to an automatic watch, the Kinetic’s oscillating weight doesn’t spin as freely as I expected. The rotor is also noisier than the typical automatic watch and sounds rather coarse to the ear.
A quick flick of the wrist and you can hear and feel the oscillating weight spinning for half a second and stopping abruptly. If you’re used to smooth-spinning oscillating weights in automatics (such as the ETA Valjoux 7750 chronograph), you’ll be terribly disappointed.
I thought it was peculiar to just my watch and later I had the chance to test other Seiko Kinetics of varying calibers at watch stores. All of them behaved similarly. Two more Seiko Kinetics later in my inventory, I’m convinced that Kinetic oscillating weights don’t spin freely like automatics.
This phenomenon is probably due to the fact the oscillating weight has a high torque load to drive those step-up multiplier gears, which in turn rotate the tiny dynamo at a mind boggling rate of 100,000rpm to generate electricity.


An exploded-view of an early Kinetic movement (note that "capacitor" is used in this example)​

When I had my SKA013P some years ago I owned about no more than two dozen watches. It was easy to discipline myself to wear it once a week. Since then my collection has more than doubled and with two more additional Kinetics, I have to force myself to wear them to avoid running down their rechargeable cells.
That said, I have since replaced the LiOn cells of my SKA013P and SMY003P because they were already dead when I purchased them. Their power reserves dropped sharply after owning them for eight months, so to be on the safe side I decided to replace them one after another.
Probably most Seiko Kinetic owners out there are one-watch folks who were attracted to the idea of a watch that needs no battery changing. I’ve met a few guys (and strangers) who wear a Kinetic and I actually asked them why they chose the watch in the first place.
Nearly half of them said they were interested in the virtually maintenance-free watch concept although they didn’t really understand how the Kinetic mechanism worked (they probably couldn’t care less anyway). As for the remainder, well… they said they chose their watches because they looked simply attractive or received them as a gift.


Why are there no more Seiko Kinetics for women?

You may have noticed that Seiko has not released Kinetic models for women for decades. Actually, Seiko Kinetics have a good market share and there shouldn’t be any reason why they shouldn’t make Kinetic watches for the ladies too. Actually Seiko did experiment with Kinetics for women (like very early 3M caliber) in the 1990s and then decided to discontinue Kinetics for ladies.
My best educated guess is - it was largely a marketing failure. Women typically consider wrist watches as accessories that tell the time. They want their watches to look good with the clothes they wear and more importantly, the watches have to be as maintenance-free as possible.
I’d say that 99% of the women I that I know personally prefer quartz watches. Unlike men, they’re not too bothered with features or the movement that runs their timepieces. They want a good-looking watch and not having to go through the trouble of winding or charging them.
I guess this explains why fashion brand watches like Guess, Swatch and Diesel are mostly quartz.
For the female consumer market, Seiko watches since then are available in either quartz or automatic format. Due to lack of interest in mechanicals, almost all Seiko timepieces for ladies are battery powered quartz. Automatic calibers constitute the minority movement and the probably the most notable automatic caliber for ladies’ watches is the 4207 caliber with auxiliary hand winding. You can find the 4207 in some women’s model from the Seiko 5 Sports range.
There’s also the limitation of the Kinetic movement itself. The internal power generator requires a rather strong torque to drive the step up gears. The only way to accomplish this is to use a large oscillating weight with sufficient mass to drive the Kinetic rotor. A small oscillating weight translates into less efficiency in charging the watch.
Seiko does have quartz calibers meant only for women’s watches but lately the company has also used the 7T92 chronograph movement designed for gents’ models. Ladies’ watches using the 7T92 quartz movement are usually larger than traditional ladies’ models.
(A big thanks to a few of my readers who pointed out that Kinetic watches for women did at one time, exist)



Direct Drive: The shape of things to come?

Very recently Seiko released a variation of its Kinetic movement - the Direct Drive Kinetic. It first debuted with the SRH-series Velatura yacht sports watches with the 5D44 caliber and shortly thereafter added the 5D22 caliber, without the retrograde day-of-week display.
What sets the Direct Drive movements from the other Kinetics is the DD’s ability to charge the internal Kinetic ESU via a hand-winding crown and the inclusion of a real-time power reserve indicator. You can regard it as an automatic movement with manual winding.
I had the opportunity to briefly inspect a dark blue dialed SRH003P Direct Drive at my watchmaker’s store. It’s a pretty large and chunky watch and its approximately USD800 list price is an indication that the movement itself accounts for a chunk of the watch’s retail price.


The Velatura SRH003P (left) with the 5D44 caliber and the 5D22-powered Premier SRG003P (right). Pictures courtesy of Chronograph.com

To be frank, I liked the attractive looks of the SRH003P but wondered if the hand winding feature of the Direct Drive was more of a novelty. The real-time power reserve indicator probably works on the principle of a logarithmic voltmeter. As I shook or manually wound the watch, I observed the power reserve jumping a few notches up and then settling down to indicate the true reserve.
My watchmaker attempted to thumb-crank the Velatura to get it to a decent charge. Ten minutes later he gave up, citing that both his thumbs were sore!
We looked at the power reserve gauge and it registered no more than a mere day’s worth of charge in spite of his efforts.
In most likelihood, if I had this watch I would probably hand wind the watch for the first two weeks. When the fun wears off, I’ll probably won’t bother with winding it manually and let my natural wrist motions do the work.


Seiko’s official diagram of a 5D44 Direct Drive. They probably didn’t proof read it before publishing. "Two hour hands" on this watch? I don’t think so.​

Then I’ll probably think, "Why buy a Direct Drive if I’m going to wear it like a regular Kinetic?". I think I were to buy a Direct Drive watch, I would buy it because I like how the watch looks rather than for its underlying technology.
The 5D44/5D22’s surprisingly unrealistically low power reserve of only 1 month raises some questions. Does the power reserve indicator use up that much energy as it measures the internal Kinetic ESU’s reserve? I can understand the 9T82’s one-month reserve as it’s a chronograph with a energy-sapping 1/10th second stopwatch subdial. Even the 7L22 Kinetic Chronograph manages a 5-month reserve.
Will Seiko replace its conventional Kinetic calibers with the likes of the Direct Drive? I personally don’t think they will. The Direct Drive movement is expensive to begin and it’s probably targeted at their upper-midrange markets. Seiko is already enjoying good worldwide sales of its more affordable range of Kinetic timepieces. Therefore I don’t suppose they’re going to disturb their proverbial cash cow.


Conclusion

We’ve come to the end of this rather long-winded post. So, is the Seiko Kinetic a boon or a bane?
It’s definitely a boon if you only need one watch or own no more than half a dozen watches, worn on daily rotation. Not to mention that you’re not the sedentary sort of person.
On the flip side, I think Kinetics are a bane if you have a large number of watches that you wear on rotation. Unlike a solar powered watch that you can recharge by merely exposing it to light, you need to wear a Kinetic as often as possible. And if you’re a physically active person, a Seiko Kinetic would be right for you.
The Seiko Kinetic is an interesting hybrid movement combining the best of mechanical and quartz technologies. You get the feel of an automatic while enjoying the accuracy of a regular, battery operated quartz. It’s almost maintenance free too and with the newer lithium ion cells it’ll be a long time before the watch needs to be sent for routine servicing.
Models using the older calibers could be easily upgraded to the more efficient LiOn rechargeable cell. The minute backlash problem that plagued the early Kinetics had since been fixed since the birth of the 5M6x series sometime in 2000.
Seiko was quite content with their perfected 5M6x caliber which is still used to this day. In fact, their engineers were confident with the design that later on when designing the 7L22 Kinetic chronograph movement, they borrowed the 5M’s power generation unit and mated it with the geartrain from their tried-and-proven 7N quartz caliber.


Three Seiko Kinetics later, I’ve decided to call it a day! From left to right, SKA013P, SMY003P and SNL035P​

If long battery life is your ultimate goal, you’ll be better off owning one of the quartz Perpetual Calendar models that Seiko sells. These watches are more accurate than your everyday quartz (+/- 20secs per year vs +/- 15secs per month!) and thanks to the disposable lithium cell, you won’t need a battery change for 10 years.
Mechanical watch purists generally shun from quartz and hybrid watches like the Kinetic (and perhaps, the almost-mechanical Seiko Spring Drive) but hey, I’m a Seiko watch enthusiast so I must have at least one Kinetic in my collection.
 

·
Registered
Joined
·
1 Posts
Hi there

This is a very informative article. Thank you. I know its been a few years now, but I was really hoping that you can help me answer a few questions. You mentioned that prior to Seiko using the Li-on battery, they had used a capacitor like cell. As far as I understand, I didn't think capacitors had solutions in its makeup to leak? Could it have been an early attempt at a rechargeable cell? Also could you please provide me with another article that mentions when Seiko changed from using the capacitors to li-on batteries. Thank you in advance for your assistance.

Best regards. D
 

·
Registered
Joined
·
14,802 Posts
Outstanding article everything one could ever want to know about Kinetics up until about 09, very interesting read, thanks OP.
 

·
Registered
Joined
·
109 Posts
Weird thing happened to me this morning, (maybe because it was Friday the 13th yesterday). I bought the Seiko SUN023 brand new back in June and wore it for quite some time. I also made sure it was fully charged up back in July (i.e. it had a 6 month power reserve). When I woke up this morning, I noticed that the watch had stopped running at 9:40 PM last night. Also, when I checked the power reserve, it was almost empty. Can anyone explain this??? Has it not been charging even though I've been wearing it since July???
 

·
Registered
Joined
·
141 Posts
Fabulous article! Cleared up many questions I had about Seiko's kinetic movement(s). I suppose only a dedicated collector would take the time to write up so many findings made over the years, and we, out here, are the lucky recipients of your dedication. Thanks a million! Bravo! Fred Halgedahl
 
1 - 9 of 9 Posts
Top