Citizen BN0176-08E PROMASTER ECO-DRIVE 300m Professional Diver's Watch:
Comprehensive Review
by BushCampingTools
I thought it was fitting to do a intensive review of this watch as it is the 30th anniversary of the PROMASTER range from Citizen Watches.
This watch was released/announced at Basel World in 2016 and is still being manufactured.
Speaking of Bassel World, , the 2020 conference cancelled due to the stupid panic over the Corona virus, see here:
Which is just crazy as.
The Citizen BN 0176-08E is the second current model (the top model is the super huge 1000m beast) in Citizen's "MARINE" section within the PROMASTER range of outdoor watches. The other two sections are "LAND" and "SKY". The sister/brother model of the BN 0176-08E is the BN 0177-05E (a fully DLC coated model but sporting Day Glo Green (Fluorescent green) minute hand and second markers (see below).
In this article I will be only reviewing the Citizen BN 0176-08E model but briefly speak about some other relevant models in this discussion/review.
See it here at the manufacturer's web site:
web site image here
Citizen Promaster Diver Black Dial caliber eco-
drive E168 quartz .
THE Citizen BN0176-08E PROMASTER ECO-DRIVE 300m Saturation Diver's Watch IS STILL LISTED AS A 2020 CURRENT MODEL ON THE JAPANESE CITIZEN WATCH SITE (WITH A RETAIL LIST PRICE OF 100,000
That's about $912 USD retail list price.
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| Outer box marked made in the USA |
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| Inner "hard box" marked Made in China! |
So I guess the watch is assembled in China????? to be sold in America, who knows?
This is a "hard to get model". Outside of Japan it seems to be sold as quickly as they are listed on various internet sites around the globe (excepting the official Citizen watch sites).
There are two distinct models within this actual watch model:
One carries the words "Japan Movt." and the caliber designation on the watch face E168 and the case back. The other, there are no markings of caliber or where the movement is made, except on the case back.
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| Case back: Note the two apposing arrows marked upon the case (base of band). These arrows indicate the direction of pin removal for this watch. The BN series does not use regular watch pins to secure the band/bracelet but instead these pins are friction fitted. The arrow indicates the direction that the pin travels to be removed. Why on earth Citizen did this, who knows? This is my only beef about this watch design. Maybe it was just not possible to build such a "monster" watch, have all the indestructibility associated with it and have some woosy bracelet pins fitted, who knows as I said? |
I note that on the Japanese website, one can find no markings upon the watch face. I read somewhere that the watch face markings mean that the watch was intended for the USA market (only?). Anyway the sister/brother model of the BN0176-08E is the following:
BN0177-05E
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| Screen shot of a current 2020 300m Helium escape valve PROMASTER ECO-DRIVE watch.(this model now discontinued according to the USA Citizen site- but NOT the BN 0176-08E watch I review here). |
This particular model sports a fully DLC (Diamond Like Carbon) coated body and the increased price reflects this, or does it? As that's ten thousand yen more!! 10,000円!, . Also as one can see the minute and second hands are fluorescent lime green. BTW this is an easy color to see at depth ie the "day glow green" ie fluorescent green, speaking from experience. Although now I wonder at what depth the fluorescent orange would disappear? I should be able to simulate this as a little experiment, if we assume that the shorter wavelengths penetrate the depths much better than the longer wavelengths (such as red). The USA Citizen site lists this model as being "discontinued" such a shame really!
But maybe it's the added cost of a full DLC coating? Afterall this model is identical time keeping wise to the watch on review here, the Citizen BN 0176-08E.
Simulated Visibility Experiment at Depth
We tested the bright yellow markers on the SEIKO PROSPEX 200M Air Diver's watch with the following wavelengths:
Violet
Blue
Extreme Wavelength Experimental Results:
And now the Citizen BN0176-08E PROMASTER 300m Saturation diver's watch.
Simulated Visibility Experiment at Depth
We tested the bright yellow markers on the SEIKO PROSPEX 200M Air Diver's watch with the following wavelengths:
Violet
Blue
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| Yellow and Fluorescent Orange markers What do they look like at depth? (daylight illumination) |
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| SEIKO Violet illumination |
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| SEIKO Closeup Violet illumination |
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| SEIKO Blue wavelength illumination |
And now the Citizen BN0176-08E PROMASTER 300m Saturation diver's watch.
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| Violet Illumination |
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| Blue wavelength illumination |
As you can see the Fluorescent Orange markers appear to be a bit more contrasty than the Seiko's yellow markers. No surprises here as the Citizen BN 0176-08E is deigned go deeper and hence more blue wavelength penetration in clear water. Plus fluorescent colours are obviously fluorescing under blue light!
The Citizen BN-0176-08E, the 300m Saturation divers watch is a HARDCORE TOOL!!
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| As the writing says, PROFESSIONAL DIVER'S |
This is a kick ass dive watch. It's a MAN's watch. Did I just say that? YES I did, its REAL MAN'S watch!
Ok, I've never dived deeper than 30 odd metres (100ft pls), so at 10 X the depth rating and maybe, just maybe one day I'll do some saturation diving (for research of course)- I am a marine biologist-past life actually by training so that old Helium escape valve might come in handy so I don't blowup my watch!
How long does the battery last in an ECO DRIVE that has seen proper charging???
I'm a big fan of the ECO DRIVE. After all, I've owned a 200M ECO-drive dive watch (Citizen 7878 movement/caliber)
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| Citizen 200m Diver's watch (missing the bezel because the mechanism simply wore out over 20 odd years of rotation for various sports, diving included-from sand and silt mostly from diving and surfing). The Citizen 7878 caliber is still going strong and keeping great time although the date mechanism seems to be a bit off? So clearly the Lithium Titanium batteries can go the distance! |
for almost 20 years and it's still working despite wearing out the Bezel ring mechanism-lost it in the surf of all things! . It has long since proven it's waterproofness and toughness: caving and diving; climbing; surfing; fishing and kayaking etc etc. Now since the Citizen BN0176-08E looks like a mega tough version of my previous ECO DRIVE then I can't see why it will not be able to handle the pace.
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| Crown of the Citizen BN 0176-08E is at the 4'oclock position, therefore unobtrusive, doesn't restrict wrist movement. |
Ok lets break down the features of this watch!
Table taken from the Japanese Citizen site.
As the above specifications indicate the BN 0176-08E features hacking for the second hand. The watch has a 6 month power reserve on full charge and the second hand moves every two seconds to indicate a low battery charge. You can not over charge this watch.
A bezel which can be easily turned even wearing (thick) dive gloves!
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| Wearing dive gloves, no problems turning the chunky bezel on the Citizen BN 0176-08E PROMASTER 300 Helium saturation diver's watch. |
The case thickness is listed as 16.7mm and here you can see what I measured. Certainly social media sites listing it as 18mm and above are somewhat ridiculous and i have no idea of where they got their figures from, probably copied them from other erroneous sites. However, here on Hardcore Knives and tools for wilderness camping, you will get the facts, not hear say!
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| Yep 16.13mm is close enough to 16.7mm. I suggest this discrepancy is due to the fact i did not measure to the top of the case back. The fact is the BN0176-08E case thickness is no where near 18mm plus as reported elsewhere on other forum sites. |
Mineral crystal watch glass. How thick is it?
Well some say 6mm thick but whatever it is (Citizen do not openly list this specification). I have asked Citizen but I got no reply to that question and many others. Citizen are not renowned for after market sales service/customer service according to many social media blogs/Forums etc.
The Bezel
Coated bezel (DLC coating, that's Diamond Like Carbon).
In other words a PVD (Physical Vapor Deposition) coating that adds some superficial hardness and scratch resistance to the Aluminium surface of the bezel. good idea for the DLC coating as this region will see a lot of use and it will help to slow down wear from abrasion (sand, silt, dirt in the water).
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| One way rotating bezel features a surface coating of DLC, that's "Diamond-Like Carbon" via a PVD process. Not only does it look cool but it is functional as well. DLC coatings work very well to help protect surfaces from light abrasive forces and corrosion. Note easily read BIG minute markers. |
Case forged (probably) Stainless steel construction.
Super bright chunky luminous markers
Helium escape valve (ISO 6425) to prevent damage from expanding
helium during saturation diving decompression.
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| Helium escape valve to allow He gas to escape without damaging the watch |
Solar Powered; no need to replace a battery as I said.
Inside is a Titanium Lithium rechargeable battery.
ECO Drive Movement E168, with date at the 4pm position (date not shown in this picture)
This is what it looks like
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| Generic Citizen E168 movement Image courtesy of Suppaparts |
The Bracelet
The urethane rubber bracelet is great. It has good flexibility and the right amount of "Tackiness" in order to provide a good secure attachment to one's wrist over a wet or dry suit. There is no way the band can come out of the two retaining loops (a common occurrence for many "rubber dive bands" when subjected to harsh movements/rubbing against diving objects and or even clothing! Especially if the end of the strap is subjected to a direct "push" against the end.
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| Rubber watch strap two strap retainers (only one shown and this one closest to the buckle is retained via two cut away sections in the band. This is a good design feature as it prevents these things from moving and hence not working properly. |
"UUUUHHH, ah.... well, actually I'm not"- he says as he shrinks into corner of room at party and looses girl's attention forever!
This is a watch to wear not to be taking on and off to show off or to be swapping out watches. It's tool and a watch to be worn 24-7!
That 247!
Ok I'm a bit tough here, as dive watches make for great super rough and tumble time pieces and one doesn't need to be a diver.....BUT at least a: surfer; rock fisherman (they always get washed in the drink!); snorkel diver (for abalone, scallops etc); caver, or some activity that gets one wet and it's action stations, but certainly NOT for the office unless you carry that credibility, IMHO! Forget the "cuffs business" if you are a diver then "cuffs it is"! Who says you can't wear a dive watch with a suit! Heck I did, and still do!
What happens if you don't like the bracelet that comes with the Citizen BN0176-08E? Well there are many aftermarket manufacturers that provide adaptors to fit just about any other band on the market; for example: SUPPAPARTS
See here for the BN series of watches
They look like this:
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| SUPPAPARTS makes adaptors for the BN series watches from Citizen-no they are not paying me to advertise them, I just found them via an internet trawl. (Image courtesy of SUPPAPARTS) |
The Citizen BN 0176-08E is a "lug-less" watch, where the supplied band is specially moulded to provide a rigid support next to the watch case. Special pins which are held in place by split spring steel tubes. What's with this design? Well since Citizen Japan neglected to answer my questions about this watch for the blog. Maybe if I called them then that would have been a little harder to do as I've never encountered anything like this when living in Japan. But I reckon it's a lug-less design because there is no chance that the lugs could get caught p in something. After all, this is a watch meant to be worn for work and work under the water, since there really isn't such a thing as "recreational saturation diving"
But wait there's more........!
Urethane is a great material for watch bands, it possesses a high tensile strength, resistant to many chemicals and extremely resistant to fatigue, fungal attack and of course tear resistance. In short an ideal material for a watch band.
OK, ok Citizen BN 0176-08E 300m diving watch is an ideal outdoor enthusiasts watch, simple, easy to read anywhere and waterproof beyond reproach (without the bulk of the 1000m model-and cost!).
Actually, a funny story (I reckon) was when I started this corporate job, the knob who was my boss (of sorts) came over to me on my first day and asked to see my shoes (I knew exactly where he was going LOL!), so I showed him:
"Ah leather soles, yeah good to see". He said, then glancing towards my tie he continued. "The tie is silk, right? What brand?"
As I proceeded to show him the Christian Dior label (which he didn't really approve of) of that 100% silk business tie (still a funky colour pattern), he caught sight of my wrist.
"Ah, no the watch (a diving watch) is not appropriate here, you need a watch like mine." He said, smiling like a complete chump! He was sporting a gold Tag Heuer dress watch, like some absolute woosy flimsy looking time piece which was about ten times the cost of my SEIKO slim line wave Quartz (shark action seen) dive watch LOL! - can you remember that model??? Ok that tells you how old I am LOL! I told him Tag Heuer dive watches were gimmicks! Needless to say he beat a hasty retreat to his fishbowl office and had it in for me for the duration of my 3 odd years there LOL!
Ok I digress!
The overall case shape of the Citizen BN 0176-08E
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| Unlike the Citizen Ecozilla, the Citizen BN 0176-08E's case is widest at it's base and narrowest at the bezel. I protected the watch crystal with a Note Pad screen protector |
The Citizen BN 0176-08E case tapers from the wrist up, not down as in the ECOZILLA, and is 1mm thinner than the ECOZILLA. The Citizen BN 0176-08E case is 48mm wide.
This in MHO is a much better design than (the
Citizen BJ8050-08E) tapering from a narrow case back to a wider watch face, it makes the watch look like a "bucket" and "top heavy".
I'm not sure why the ECOZILLA has such a following and also the large amount of 3rd part modifications available for it. maybe it's just the retro looking design but it still looks like a bucket LOL IMHO (No offense really to all ECO ZILLA owners and lovers)
On Design
Cutaways on the minute and hour hands to allow light to get at the smaller solar panel (smaller than the ECOZILLA).
Big fluorescent orange minute hand to easily see elapsed dive minutes. Impossible to get wrong even in dim light/murky waters/darkness (with torch/flashlight of course!).
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Huge fluorescent orange minute hand, easily see elapsed dive minutes. Note the "cutaway" in the minute hand (the hour hand also has a cut out section but it is hard to see in the image). This is done to allow optimal light exposure on the ECO Drive solar cell. The actual solar cell of this beast is quite small compared to the Citizen ECO ZILLA.
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| Huge chunky super bright luminous hour markers, easily seen for night diving or any activity in total darkness. |
Where does the Citizen BN 0176-08E 300m ECO-DRIVE saturation divers watch sit within the current 2020 Professional Diving watch range?
See details second from bottom (above table), see 300m waterproof He-Gas DIVER'S 300M. NOTE the text states, "Air tight structure against Helium gas, which basically means if you unscrew the crown to this watch whilst in the chamber/bell and Helium enters, then it can later harmlessly (the the watch) escape. However, if you do not unscrew the crown whilst in the chamber/bell then Helium gas can not enter the watches' structure. BTW I found this information on the Japanese language website for Citizen Japan and used Google translator for the English version seen above.
How does the helium escape valve work?
It simply allows the super small molecules of helium gas to escape and prevents much much larger molecules of water under pressure from entering the watch at depth.
As one well known writer (Ed ESTLOW) of watch reviews said:
"And let’s be honest. With the availability of modern dive computers, the dive watch as a vital diving tool is an anachronism"
This is of course complete Bullsh&t! and hardly "old fashioned". If you are a serious diver, regardless of how many computers you own and how good you are with dive computers, you will be wearing that dive watch. In fact I'm afraid to dive with anyone who only sports a computer. Here are my reasons: Firstly, dive computers can be damaged by being carelessly looked after, not serviced calibrated, checked against other reliable dive computers/bashed in the boat etc. Casing leaks etc. if any of this happens whilst diving with only buddies who sport dive computers, you are screwed without a watch to calculate times etc. So has this actually happened to me or am I speaking off the top of my head, speaking out of my behind? Trying to be a scare monger? YES, it has happened to me on a dive and it was during a repetitive dive, on the surface (so lucky!) where one of the other teams (there were 4 of us, 2 teams of 2, of course!) dive computer was malfunctioning! Ok, out came the tables but wait they were not wearing watches! Ok this scenario only has to happen once I reckon for one not to get caught out in the future, This was a lucky situation as we were all back at the surface, and actually no need to do the second dive (we did anyway- I think I remember a borrowed watch from the dive staff on board).
BTW I never throw myself watch arm leading into the dive boat so as to crack my watch hard against some surface in the boat, nor do I throw my watch or gear onto my arm in a dive bucket of gear to damage my watch. Get my point about wearing a dive watch?
The other place a dive watch IMHO based upon over 35 years of caving, including 2 expeditions; is during exactly that: CAVING. Especially super wet caves. Abseiling through waterfalls, swimming duck unders, mud grit, vibration, accidental banging of arms etc against gear bags or whatever, one needs to be able to tell the time underground - WHY? because you have to be able to know how long your lights are going to last, that's why; and a serious dive watch is the choice of tools for serious 24 hour plus caving expeditions.
Mr Estlow (who is not a diver) goes on to say that according to one of his diving mates, the helium escape valve only presents a liability for the dive watch failing. ABSOLUTE BS! What kind of a diver-must be a novice or armchair diver, would suggest this??? It simply doesn't make any sense at all! A one way valve is a one way valve, end of story. The helium escape valves on respected watches like the Citizen BN 0176-08E are built to a standard.
One more thing Ed Estlow goes onto say is that most "divers" in America are of the "corporate cube" type! LOL! I thought this was so funny (see my story above-ok he wasn't wearing a dive watch), who knows maybe it is the truth. In fact, I bought the model in question here, the Citizen BN 0176-08E from a guy who had never worn it near any water let alone dived with it by his own admission but was a bit of a "watch fan"! That's ok to be a collector, I guess.
Here (below) just for reference is the watches that sit above the 800M model (discontinued?) and this blogged model, the Citizen BN 0176-08E 300m watch:
A comparison between an air divers watch such as my SEIKO automatic Prospex 200m dive watch featuring a 4R36 24 jewel automatic movement and the Citizen ECO DRVE BN 0176-08E (solar) E168 movement.
The watch caliber/movement is Quartz oscillator E168, with a stated accuracy of: ±15 sec. per month. Accuracy will be dependent upon ambient temperature fluctuations.
Both a "biggish" watches but NOT really that big.
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| Who says dive watches are too chunky to wear everyday. The fact is they are meant to be worn everyday. These kinds of watches ARE TOOLS |
Charging time (see table below)
Now let's get this right for solar powered watches!
You need to put the watch into FULL SUNLIGHT if you really want to charge it properly and quickly. I mean full sunlight, like the blazing sunlight in AUSTRALIA LOL! Forget stupid LED lights etc. You'll never charge your solar watch like that, and certainly do not under any circumstances charge your solar watch under an incandescent light bulb unless you want to roast the battery! (one of the most common service issues). OR DO NOT charge the watch by leaving it on the dash of your car unless you want a well done cooked watch with a fried side order of battery! The dash can become well over 120F and over 60C! Do not place your ECO DRIVE on a rock in the sun either to charge it, the rock will cook it! Do not place it behind a window unless the back of the watch sees a lot of air movement to keep it cool! In short the safest way to charge it is upon your wrist (against your skin) and that way the watch can not go over 37C!-unless you are running a temperature or you are dead.
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| Late afternoon winter sun is ok and the watch will/should not get hot. You don't want it to get hot at all. If you charge it on morning full sun, Summer sunlight then u must protect the watch from getting hot. Pictured here is the Missus's Casio Protrek, showing a full charge (indicated by the small H-under the 21) and my Citizen BN 0176-08E. Note that the Casio when it was fully discharged took 15 hours of super bright Summer Sunlight (Australia) to achieve the "H" mark, meaning fully charged. The Citizen BN 0176-08E say about 11 hours from full discharge. I got (and it's still working) over 20 years from my other ECO DRIVE but I have been careful to make sure it never displayed the 2 second low charge indicator and that the watch was always exposed to full sunlight on my wrist. if you want to get the most from your ECO DRIVE then I'd follow that regime as close as practically possible. |
Where is it made??? Certainly ALL of the parts are MADE IN JAPAN by Citizen.
The caliber E168 says it's made in JAPAN, however, the place of assembly is a little bit harder to ascertain however, it doesn't really matter does it?; they are built to a standard and this is Citizen's top of the range dive watches for professional divers, whose lives depend upon zero equipment failures, as one saturation diver told me in relation to his back up gas supply: "If I'm going to need this at depth and distance to get back to the bell, I'm going to be fu%k$d in zero viz water"!
Can you hear the E186 mechanism? It's very silent!
Well my ears can just pick up a ticking sound but this could be because of my age (although my young son tells me it is almost inaudible) and of course due to the case thickness.
What are the positives about the Citizen BN 0176-08E PROMASTER 300m watch?
The bezel is very easy to grab ahold of and this makes a huge difference to ease of use. There is a reassuring "click" to be heard and felt on every second mark.
Stylish smooth case design, nothing to catch upon any materials.
Easy to read at depth
Bracelet which doesn't easily come undone at all.- This is a plus for divers.
ECO DRIVE of course no stuffing with a battery every 3 years or less. This is a Big Big Plus IMH and experienced opinion regarding ECO DRIVE watches and battery powered watches in general.
Tough metal construction
What are the negatives of the Citizen BN 0176-08E PROMASTER 300m saturation diver's watch?
The hour hand is a bit too much like the hour markers in size and the same color of course (offers little contrast), because both sport large amounts of luminous phosphor. Of course for diving the minute hand is the most important for up to 60min worth of diving. Obviously, for saturation diving where one could be out of the bell for many hours duration, this is irrelevant.
At a quick glance at certain hand positions, it can be a bit hard to quickly read the time, especially when the minute hand covers the hour hand, one might be at first looking at the rest of the dial to see if in fact the hour hand is located there.
Citizen use some sort of non standard fixing mechanism in order to attach the bracelet. A pin (there are two of course) which must be removed with a pin punch and special plastic headed hammer, in order to replace the band/retro fit adaptors which can take regular type watch straps. This is a procedure that shouldn't be undertaken unless you are very confident about what you are doing and or not possessing three thumbs per hand!
Here I show only for "entertainment" the following series of images from SUPPAPARTS on their guide to replacing the original watch strap.
Summary
BushCampingTools telling it how it is for hardcore outdoor products! (that he actually uses LOL!).
